Added a few files to explorer fuzzer corpus (top files by size after converting from explorer test_data sources) (#1236)

Generated with:

$ bazel build explorer/fuzzing:fuzzverter
$ cd explorer/testdata/

$ find . -name "*.carbon" | while read t; do mkdir -p "/tmp/fuzzer_corpus/$(dirname $t)" && ../../bazel-bin/explorer/fuzzing/fuzzverter --mode carbon_to_proto --input $t --output "/tmp/fuzzer_corpus/$(dirname $t)/$(basename $t .carbon).textproto" ; done

$ du -ah /tmp/fuzzer_corpus/ | grep -v fail_ | grep textproto | sort -rh | head -32 | cut -f 2 | while read t; do cp $t ../fuzzing/fuzzer_corpus/`shasum $t | cut -d ' ' -f1`.textproto; done

Tested:
$ bazel test -k explorer/...

explorer/fuzzing/fuzzer_corpus/005b7719430b22589b085fb4317c31640e6a0a8d.textproto

@@ -0,0 +1,1078 @@
+compilation_unit {
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+    package_name: "ExplorerTest"
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+}

explorer/fuzzing/fuzzer_corpus/09e83bb511e0d695ff3608a746040ae7c69cc984.textproto

@@ -0,0 +1,260 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    function {
+      name: "map"
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+        name: "T"
+        type {
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+                    return_type {
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+                        fields {
+                          index {
+                            aggregate {
+                              identifier {
+                                name: "tuple"
+                              }
+                            }
+                            offset {
+                              int_literal {
+                                value: 1
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "inc"
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Add
+                arguments {
+                  identifier {
+                    name: "x"
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 1
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              index {
+                aggregate {
+                  call {
+                    function {
+                      identifier {
+                        name: "map"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "inc"
+                          }
+                        }
+                        fields {
+                          tuple_literal {
+                            fields {
+                              int_literal {
+                                value: 0
+                              }
+                            }
+                            fields {
+                              int_literal {
+                                value: 2
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                offset {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/1a947afd765d1dff390e125d1420e20c19328b8e.textproto

@@ -0,0 +1,189 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "t"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              tuple_literal {
+                fields {
+                  tuple_literal {
+                    fields {
+                      int_literal {
+                        value: 1
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 2
+                      }
+                    }
+                  }
+                }
+                fields {
+                  tuple_literal {
+                    fields {
+                      int_literal {
+                        value: 3
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 4
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          match {
+            expression {
+              identifier {
+                name: "t"
+              }
+            }
+            clauses {
+              pattern {
+                tuple_pattern {
+                  fields {
+                    tuple_pattern {
+                      fields {
+                        binding_pattern {
+                          name: "a"
+                          type {
+                            auto_pattern {
+                            }
+                          }
+                        }
+                      }
+                      fields {
+                        binding_pattern {
+                          name: "b"
+                          type {
+                            auto_pattern {
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                  fields {
+                    binding_pattern {
+                      name: "c"
+                      type {
+                        auto_pattern {
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statement {
+                return_statement {
+                  expression {
+                    primitive_operator {
+                      op: Add
+                      arguments {
+                        primitive_operator {
+                          op: Sub
+                          arguments {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                primitive_operator {
+                                  op: Sub
+                                  arguments {
+                                    identifier {
+                                      name: "a"
+                                    }
+                                  }
+                                  arguments {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                index {
+                                  aggregate {
+                                    identifier {
+                                      name: "c"
+                                    }
+                                  }
+                                  offset {
+                                    int_literal {
+                                      value: 0
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            index {
+                              aggregate {
+                                identifier {
+                                  name: "c"
+                                }
+                              }
+                              offset {
+                                int_literal {
+                                  value: 1
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                      arguments {
+                        int_literal {
+                          value: 2
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              int_literal {
+                value: 1
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/1f6ec7038b7bc8ebd4d5778566dde5445804bbf7.textproto

@@ -0,0 +1,346 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    variable {
+      binding {
+        name: "current"
+        type {
+          expression_pattern {
+            expression {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+      initializer {
+        int_literal {
+          value: 0
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "CountUpTo"
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          if_statement {
+            condition {
+              primitive_operator {
+                op: Eq
+                arguments {
+                  identifier {
+                    name: "x"
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+            then_block {
+              statements {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "current"
+                    }
+                  }
+                  rhs {
+                    int_literal {
+                      value: 0
+                    }
+                  }
+                }
+              }
+              statements {
+                await_statement {
+                }
+              }
+              statements {
+                return_statement {
+                  expression {
+                    int_literal {
+                      value: 0
+                    }
+                  }
+                }
+              }
+            }
+            else_block {
+              statements {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "current"
+                    }
+                  }
+                  rhs {
+                    primitive_operator {
+                      op: Add
+                      arguments {
+                        int_literal {
+                          value: 1
+                        }
+                      }
+                      arguments {
+                        call {
+                          function {
+                            identifier {
+                              name: "CountUpTo"
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                              fields {
+                                primitive_operator {
+                                  op: Sub
+                                  arguments {
+                                    identifier {
+                                      name: "x"
+                                    }
+                                  }
+                                  arguments {
+                                    int_literal {
+                                      value: 1
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statements {
+                await_statement {
+                }
+              }
+              statements {
+                return_statement {
+                  expression {
+                    identifier {
+                      name: "current"
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          continuation {
+            name: "k"
+            body {
+              statements {
+                expression_statement {
+                  expression {
+                    call {
+                      function {
+                        identifier {
+                          name: "CountUpTo"
+                        }
+                      }
+                      argument {
+                        tuple_literal {
+                          fields {
+                            int_literal {
+                              value: 5
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "sum"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "count"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              int_literal {
+                value: 5
+              }
+            }
+          }
+        }
+        statements {
+          while_statement {
+            condition {
+              primitive_operator {
+                op: Not
+                arguments {
+                  primitive_operator {
+                    op: Eq
+                    arguments {
+                      identifier {
+                        name: "count"
+                      }
+                    }
+                    arguments {
+                      int_literal {
+                        value: 0
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            body {
+              statements {
+                run {
+                  argument {
+                    identifier {
+                      name: "k"
+                    }
+                  }
+                }
+              }
+              statements {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "sum"
+                    }
+                  }
+                  rhs {
+                    primitive_operator {
+                      op: Add
+                      arguments {
+                        identifier {
+                          name: "sum"
+                        }
+                      }
+                      arguments {
+                        identifier {
+                          name: "current"
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statements {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "count"
+                    }
+                  }
+                  rhs {
+                    primitive_operator {
+                      op: Sub
+                      arguments {
+                        identifier {
+                          name: "count"
+                        }
+                      }
+                      arguments {
+                        int_literal {
+                          value: 1
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              identifier {
+                name: "sum"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/2325b93a7572c5e6da46c25c8653153b7058a58a.textproto

@@ -0,0 +1,305 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    choice {
+      name: "Ints"
+      alternatives {
+        name: "None"
+        signature {
+          tuple_literal {
+          }
+        }
+      }
+      alternatives {
+        name: "One"
+        signature {
+          tuple_literal {
+            fields {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+      alternatives {
+        name: "Two"
+        signature {
+          tuple_literal {
+            fields {
+              int_type_literal {
+              }
+            }
+            fields {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              tuple_pattern {
+                fields {
+                  var_pattern {
+                    pattern {
+                      alternative_pattern {
+                        choice_type {
+                          identifier {
+                            name: "Ints"
+                          }
+                        }
+                        alternative_name: "Two"
+                        arguments {
+                          fields {
+                            binding_pattern {
+                              name: "a1"
+                              type {
+                                auto_pattern {
+                                }
+                              }
+                            }
+                          }
+                          fields {
+                            var_pattern {
+                              pattern {
+                                binding_pattern {
+                                  name: "a2"
+                                  type {
+                                    auto_pattern {
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                fields {
+                  tuple_pattern {
+                    fields {
+                      tuple_pattern {
+                        fields {
+                          binding_pattern {
+                            name: "b"
+                            type {
+                              auto_pattern {
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          var_pattern {
+                            pattern {
+                              binding_pattern {
+                                name: "c"
+                                type {
+                                  auto_pattern {
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      var_pattern {
+                        pattern {
+                          tuple_pattern {
+                            fields {
+                              binding_pattern {
+                                name: "d"
+                                type {
+                                  auto_pattern {
+                                  }
+                                }
+                              }
+                            }
+                            fields {
+                              binding_pattern {
+                                name: "e"
+                                type {
+                                  auto_pattern {
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              tuple_literal {
+                fields {
+                  call {
+                    function {
+                      field_access {
+                        field: "Two"
+                        aggregate {
+                          identifier {
+                            name: "Ints"
+                          }
+                        }
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          int_literal {
+                            value: 1
+                          }
+                        }
+                        fields {
+                          int_literal {
+                            value: 10
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                fields {
+                  tuple_literal {
+                    fields {
+                      tuple_literal {
+                        fields {
+                          int_literal {
+                            value: 2
+                          }
+                        }
+                        fields {
+                          int_literal {
+                            value: 3
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      tuple_literal {
+                        fields {
+                          int_literal {
+                            value: 4
+                          }
+                        }
+                        fields {
+                          int_literal {
+                            value: 5
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "a1"
+              }
+            }
+            rhs {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "a2"
+              }
+            }
+            rhs {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "c"
+              }
+            }
+            rhs {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "d"
+              }
+            }
+            rhs {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "e"
+              }
+            }
+            rhs {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/28a2369341442b82638b49da26c63af7dc4a87a3.textproto

@@ -0,0 +1,494 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    choice {
+      name: "Ints"
+      alternatives {
+        name: "None"
+        signature {
+          tuple_literal {
+          }
+        }
+      }
+      alternatives {
+        name: "One"
+        signature {
+          tuple_literal {
+            fields {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+      alternatives {
+        name: "Two"
+        signature {
+          tuple_literal {
+            fields {
+              int_type_literal {
+              }
+            }
+            fields {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "x"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "None"
+                    aggregate {
+                      identifier {
+                        name: "Ints"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "y"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "One"
+                    aggregate {
+                      identifier {
+                        name: "Ints"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      int_literal {
+                        value: 42
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "n"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          match {
+            expression {
+              identifier {
+                name: "y"
+              }
+            }
+            clauses {
+              pattern {
+                expression_pattern {
+                  expression {
+                    field_access {
+                      field: "None"
+                      aggregate {
+                        identifier {
+                          name: "Ints"
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statement {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "n"
+                    }
+                  }
+                  rhs {
+                    primitive_operator {
+                      op: Add
+                      arguments {
+                        identifier {
+                          name: "n"
+                        }
+                      }
+                      arguments {
+                        int_literal {
+                          value: 2
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            clauses {
+              pattern {
+                alternative_pattern {
+                  choice_type {
+                    identifier {
+                      name: "Ints"
+                    }
+                  }
+                  alternative_name: "One"
+                  arguments {
+                    fields {
+                      binding_pattern {
+                        name: "x"
+                        type {
+                          auto_pattern {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statement {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "n"
+                    }
+                  }
+                  rhs {
+                    primitive_operator {
+                      op: Sub
+                      arguments {
+                        primitive_operator {
+                          op: Add
+                          arguments {
+                            identifier {
+                              name: "x"
+                            }
+                          }
+                          arguments {
+                            int_literal {
+                              value: 1
+                            }
+                          }
+                        }
+                      }
+                      arguments {
+                        int_literal {
+                          value: 42
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            clauses {
+              pattern {
+                alternative_pattern {
+                  choice_type {
+                    identifier {
+                      name: "Ints"
+                    }
+                  }
+                  alternative_name: "Two"
+                  arguments {
+                    fields {
+                      binding_pattern {
+                        name: "a"
+                        type {
+                          auto_pattern {
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      binding_pattern {
+                        name: "b"
+                        type {
+                          auto_pattern {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statement {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "n"
+                    }
+                  }
+                  rhs {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          match {
+            expression {
+              identifier {
+                name: "x"
+              }
+            }
+            clauses {
+              pattern {
+                alternative_pattern {
+                  choice_type {
+                    identifier {
+                      name: "Ints"
+                    }
+                  }
+                  alternative_name: "One"
+                  arguments {
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+                      binding_pattern {
+                        name: "x"
+                        type {
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+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statement {
+                assign {
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+                    identifier {
+                      name: "n"
+                    }
+                  }
+                  rhs {
+                    primitive_operator {
+                      op: Add
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+                        identifier {
+                          name: "x"
+                        }
+                      }
+                      arguments {
+                        int_literal {
+                          value: 2
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            clauses {
+              pattern {
+                expression_pattern {
+                  expression {
+                    call {
+                      function {
+                        field_access {
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+                          aggregate {
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+                  rhs {
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+                        identifier {
+                          name: "n"
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+                      }
+                      arguments {
+                        int_literal {
+                          value: 1
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            clauses {
+              pattern {
+                alternative_pattern {
+                  choice_type {
+                    identifier {
+                      name: "Ints"
+                    }
+                  }
+                  alternative_name: "Two"
+                  arguments {
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+                        name: "x"
+                        type {
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+                    fields {
+                      binding_pattern {
+                        name: "y"
+                        type {
+                          auto_pattern {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              statement {
+                assign {
+                  lhs {
+                    identifier {
+                      name: "n"
+                    }
+                  }
+                  rhs {
+                    int_literal {
+                      value: 5
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              identifier {
+                name: "n"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    choice {
+      name: "MoreInts"
+      alternatives {
+        name: "None"
+        signature {
+          tuple_literal {
+          }
+        }
+      }
+      alternatives {
+        name: "One"
+        signature {
+          tuple_literal {
+            fields {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+      alternatives {
+        name: "Two"
+        signature {
+          tuple_literal {
+            fields {
+              int_type_literal {
+              }
+            }
+            fields {
+              int_type_literal {
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/33efe22bddf410c088efa3abe4eb511e1f1f2507.textproto

@@ -0,0 +1,637 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Zero"
+              param_pattern {
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            int_literal {
+                              value: 0
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            int_literal {
+                              value: 0
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
+                      expression_pattern {
+                        expression {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
+                    type {
+                      expression_pattern {
+                        expression {
+                          int_type_literal {
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+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "a"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "Scale"
+                    aggregate {
+                      call {
+                        function {
+                          field_access {
+                            field: "Add"
+                            aggregate {
+                              identifier {
+                                name: "a"
+                              }
+                            }
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              call {
+                                function {
+                                  field_access {
+                                    field: "Zero"
+                                    aggregate {
+                                      identifier {
+                                        name: "T"
+                                      }
+                                    }
+                                  }
+                                }
+                                argument {
+                                  tuple_literal {
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "s"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 10
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/3529941f593ea85e31a53c15774d54bc728ef54c.textproto

@@ -0,0 +1,678 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
+                      expression_pattern {
+                        expression {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
+                    type {
+                      expression_pattern {
+                        expression {
+                          int_type_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "t"
+            type {
+              expression_pattern {
+                expression {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "T"
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+                    }
+                    fields {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "m"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Add"
+                aggregate {
+                  index {
+                    aggregate {
+                      identifier {
+                        name: "t"
+                      }
+                    }
+                    offset {
+                      int_literal {
+                        value: 0
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "n"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Scale"
+                aggregate {
+                  call {
+                    function {
+                      identifier {
+                        name: "m"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          index {
+                            aggregate {
+                              identifier {
+                                name: "t"
+                              }
+                            }
+                            offset {
+                              int_literal {
+                                value: 1
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "n"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "s"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
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+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
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+                fields {
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+                  expression {
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+                      value: 1
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "b"
+                type {
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+                      identifier {
+                        name: "Point"
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+              }
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+                  expression {
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+                  expression {
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+                      value: 3
+                    }
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+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "a"
+                          }
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+                        fields {
+                          identifier {
+                            name: "b"
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 15
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/4ac057f4d857b6644a3de54266d932940ebf106a.textproto

@@ -0,0 +1,696 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
+                      expression_pattern {
+                        expression {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
+                    type {
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+                        expression {
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+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "a"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "b"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "m"
+                type {
+                  expression_pattern {
+                    expression {
+                      function_type {
+                        parameter {
+                          tuple_literal {
+                            fields {
+                              identifier {
+                                name: "T"
+                              }
+                            }
+                          }
+                        }
+                        return_type {
+                          identifier {
+                            name: "T"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Add"
+                aggregate {
+                  identifier {
+                    name: "a"
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "n"
+                type {
+                  expression_pattern {
+                    expression {
+                      function_type {
+                        parameter {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                        return_type {
+                          identifier {
+                            name: "T"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Scale"
+                aggregate {
+                  call {
+                    function {
+                      identifier {
+                        name: "m"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "b"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "n"
+                  }
+                }
+                argument {
+                  tuple_literal {
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+                      identifier {
+                        name: "s"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 3
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "b"
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 15
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/50f4f5f704edc5df5c52f6c61da5b8d0831833c9.textproto

@@ -0,0 +1,671 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Scalar"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point"
+            }
+          }
+          interface {
+            call {
+              function {
+                identifier {
+                  name: "Vector"
+                }
+              }
+              argument {
+                tuple_literal {
+                  fields {
+                    int_type_literal {
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Zero"
+              param_pattern {
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            int_literal {
+                              value: 0
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            int_literal {
+                              value: 0
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
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+                          expression {
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+                    name: "Point"
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+                        fields {
+                          name: "x"
+                          expression {
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+                              op: Mul
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+                                      name: "me"
+                                    }
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+                              arguments {
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+                                  name: "v"
+                                }
+                              }
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+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
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+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
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+    }
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+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
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+        }
+      }
+      deduced_parameters {
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+        type {
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+              identifier {
+                name: "Vector"
+              }
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+                  }
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+            name: "a"
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+              }
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+          }
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+        fields {
+          binding_pattern {
+            name: "s"
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+        }
+      }
+      return_term {
+        kind: Expression
+        type {
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+            name: "U"
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+                  field_access {
+                    field: "Scale"
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+                          field_access {
+                            field: "Add"
+                            aggregate {
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+                                name: "a"
+                              }
+                            }
+                          }
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+                        argument {
+                          tuple_literal {
+                            fields {
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+                                  field_access {
+                                    field: "Zero"
+                                    aggregate {
+                                      identifier {
+                                        name: "U"
+                                      }
+                                    }
+                                  }
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+                                argument {
+                                  tuple_literal {
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+      param_pattern {
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+      return_term {
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+        type {
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+          variable_definition {
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+              binding_pattern {
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+                type {
+                  expression_pattern {
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+                      identifier {
+                        name: "Point"
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+                    name: "AddAndScaleGeneric"
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+                      identifier {
+                        name: "a"
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+                    fields {
+                      int_literal {
+                        value: 5
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+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
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+                    value: 10
+                  }
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+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/68e19dcc4cfb876cb2501c6d9617e9bc24d72428.textproto

@@ -0,0 +1,686 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
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+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
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+        variable {
+          binding {
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+      members {
+        variable {
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+            type {
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+          }
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+      }
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+  }
+  declarations {
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+      kind: ExternalImpl
+      impl_type {
+        call {
+          function {
+            identifier {
+              name: "Point"
+            }
+          }
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+                int_type_literal {
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+      members {
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+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
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+          body {
+            statements {
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+                  struct_literal {
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+                      expression {
+                        int_literal {
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+                    }
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+                  }
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+                      expression {
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+                                  name: "me"
+                                }
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+                      expression {
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+                                  name: "me"
+                                }
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+                          }
+                          arguments {
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+        function {
+          name: "Scale"
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+                    name: "Self"
+                  }
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+                              field: "x"
+                              aggregate {
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+                            }
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+                          op: Mul
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+                              aggregate {
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+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
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+    function {
+      name: "AddAndScaleGeneric"
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+          }
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+                                name: "a"
+                              }
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+                                        name: "T"
+                                      }
+                                    }
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+                                argument {
+                                  tuple_literal {
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+      param_pattern {
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+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
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+                name: "a"
+                type {
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+                      call {
+                        function {
+                          identifier {
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+        statements {
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+            pattern {
+              binding_pattern {
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+                type {
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+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
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+                              int_type_literal {
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+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
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+                    fields {
+                      identifier {
+                        name: "a"
+                      }
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+                      }
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+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
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+              primitive_operator {
+                op: Sub
+                arguments {
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+                    aggregate {
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+                      }
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+                    value: 10
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/6b5ba4e640c19e8d032e662194f8c5bbfd7ff4b7.textproto

@@ -0,0 +1,970 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
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+          param_pattern {
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+              binding_pattern {
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+                type {
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+                      identifier {
+                        name: "Self"
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+                }
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+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
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+          }
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+        variable {
+          binding {
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+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              identifier {
+                name: "Number"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  primitive_operator {
+                    op: Add
+                    arguments {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                    arguments {
+                      identifier {
+                        name: "other"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        call {
+          function {
+            identifier {
+              name: "Point"
+            }
+          }
+          argument {
+            tuple_literal {
+              fields {
+                identifier {
+                  name: "U"
+                }
+              }
+            }
+          }
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "U"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "U"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "U"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "U"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              identifier {
+                                name: "U"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "U"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Add"
+                              aggregate {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                              fields {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "other"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Add"
+                              aggregate {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                              fields {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "other"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Sum"
+      deduced_parameters {
+        name: "E"
+        type {
+          identifier {
+            name: "Number"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "E"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "E"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "E"
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "total"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "E"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Zero"
+                    aggregate {
+                      identifier {
+                        name: "E"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "total"
+              }
+            }
+            rhs {
+              call {
+                function {
+                  field_access {
+                    field: "Add"
+                    aggregate {
+                      identifier {
+                        name: "total"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "x"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "total"
+              }
+            }
+            rhs {
+              call {
+                function {
+                  field_access {
+                    field: "Add"
+                    aggregate {
+                      identifier {
+                        name: "total"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "y"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              identifier {
+                name: "total"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "SumPoints"
+      deduced_parameters {
+        name: "E"
+        type {
+          identifier {
+            name: "Number"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "p"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "E"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "q"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "E"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          call {
+            function {
+              identifier {
+                name: "Point"
+              }
+            }
+            argument {
+              tuple_literal {
+                fields {
+                  identifier {
+                    name: "E"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "Sum"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "q"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "q"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 4
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 3
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "r"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "SumPoints"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "q"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "r"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  field_access {
+                    field: "y"
+                    aggregate {
+                      identifier {
+                        name: "r"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/6d67acbc349af1d8c183162793004dd676007700.textproto

@@ -0,0 +1,242 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "cond"
+                type {
+                  expression_pattern {
+                    expression {
+                      if_expression {
+                        condition {
+                          bool_literal {
+                            value: true
+                          }
+                        }
+                        then_expression {
+                          bool_type_literal {
+                          }
+                        }
+                        else_expression {
+                          int_type_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              bool_literal {
+                value: true
+              }
+            }
+          }
+        }
+        statements {
+          if_statement {
+            condition {
+              if_expression {
+                condition {
+                  identifier {
+                    name: "cond"
+                  }
+                }
+                then_expression {
+                  bool_literal {
+                    value: true
+                  }
+                }
+                else_expression {
+                  bool_literal {
+                    value: false
+                  }
+                }
+              }
+            }
+            then_block {
+            }
+          }
+        }
+        statements {
+          while_statement {
+            condition {
+              if_expression {
+                condition {
+                  identifier {
+                    name: "cond"
+                  }
+                }
+                then_expression {
+                  bool_literal {
+                    value: false
+                  }
+                }
+                else_expression {
+                  bool_literal {
+                    value: true
+                  }
+                }
+              }
+            }
+            body {
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              if_expression {
+                condition {
+                  if_expression {
+                    condition {
+                      identifier {
+                        name: "cond"
+                      }
+                    }
+                    then_expression {
+                      primitive_operator {
+                        op: Or
+                        arguments {
+                          bool_literal {
+                            value: true
+                          }
+                        }
+                        arguments {
+                          bool_literal {
+                            value: false
+                          }
+                        }
+                      }
+                    }
+                    else_expression {
+                      primitive_operator {
+                        op: And
+                        arguments {
+                          bool_literal {
+                            value: false
+                          }
+                        }
+                        arguments {
+                          bool_literal {
+                            value: true
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                then_expression {
+                  if_expression {
+                    condition {
+                      primitive_operator {
+                        op: Not
+                        arguments {
+                          identifier {
+                            name: "cond"
+                          }
+                        }
+                      }
+                    }
+                    then_expression {
+                      primitive_operator {
+                        op: Add
+                        arguments {
+                          int_literal {
+                            value: 1
+                          }
+                        }
+                        arguments {
+                          int_literal {
+                            value: 2
+                          }
+                        }
+                      }
+                    }
+                    else_expression {
+                      primitive_operator {
+                        op: Mul
+                        arguments {
+                          int_literal {
+                            value: 3
+                          }
+                        }
+                        arguments {
+                          int_literal {
+                            value: 4
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                else_expression {
+                  if_expression {
+                    condition {
+                      primitive_operator {
+                        op: Not
+                        arguments {
+                          identifier {
+                            name: "cond"
+                          }
+                        }
+                      }
+                    }
+                    then_expression {
+                      primitive_operator {
+                        op: Add
+                        arguments {
+                          int_literal {
+                            value: 5
+                          }
+                        }
+                        arguments {
+                          int_literal {
+                            value: 6
+                          }
+                        }
+                      }
+                    }
+                    else_expression {
+                      primitive_operator {
+                        op: Mul
+                        arguments {
+                          int_literal {
+                            value: 7
+                          }
+                        }
+                        arguments {
+                          int_literal {
+                            value: 8
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/789bdcd9bd46dba4009d8ff3675626e31aa6ddfb.textproto

@@ -0,0 +1,799 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              identifier {
+                name: "Number"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
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+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/7b0d42569dbd71ab4f75c8d3560989b048214a58.textproto

@@ -0,0 +1,637 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
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+          return_term {
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+                name: "Self"
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+            }
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+            }
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+          members {
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+                              arguments {
+                                identifier {
+                                  name: "v"
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+                          name: "y"
+                          expression {
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+                              op: Mul
+                              arguments {
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+                                  aggregate {
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+                                      name: "me"
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+                                identifier {
+                                  name: "v"
+                                }
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+                }
+              }
+            }
+          }
+        }
+      }
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+                                name: "a"
+                              }
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+                                    aggregate {
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+                                        name: "T"
+                                      }
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+                      identifier {
+                        name: "Point"
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+                }
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+                    name: "AddAndScaleGeneric"
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+                      }
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+                        value: 5
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+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 10
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/8036c3a3216c2ed984cf5bbb86aa44df2dcad83c.textproto

@@ -0,0 +1,501 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "AddWith"
+      members {
+        function {
+          name: "Op"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: InternalImpl
+      impl_type {
+        identifier {
+          name: "Point"
+        }
+      }
+      interface {
+        call {
+          function {
+            identifier {
+              name: "AddWith"
+            }
+          }
+          argument {
+            tuple_literal {
+              fields {
+                identifier {
+                  name: "Self"
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Op"
+          me_pattern {
+            name: "me"
+            type {
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+                expression {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
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+              binding_pattern {
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+            }
+          }
+          return_term {
+            kind: Expression
+            type {
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+                name: "Point"
+              }
+            }
+          }
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+                      expression {
+                        primitive_operator {
+                          op: Add
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+                              field: "x"
+                              aggregate {
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+                                  name: "me"
+                                }
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+                            }
+                          }
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+                            field_access {
+                              field: "x"
+                              aggregate {
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+                                  name: "b"
+                                }
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+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
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+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "b"
+                                }
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "DoAddGeneric"
+      deduced_parameters {
+        name: "T"
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+        }
+      }
+      deduced_parameters {
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+              }
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+                  }
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+      }
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+            }
+          }
+        }
+        fields {
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+            type {
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+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
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+            name: "U"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
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+                    aggregate {
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+                        name: "a"
+                      }
+                    }
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+                      }
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+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 4
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "DoAddGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "b"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  primitive_operator {
+                    op: Sub
+                    arguments {
+                      field_access {
+                        field: "x"
+                        aggregate {
+                          identifier {
+                            name: "p"
+                          }
+                        }
+                      }
+                    }
+                    arguments {
+                      field_access {
+                        field: "y"
+                        aggregate {
+                          identifier {
+                            name: "p"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 3
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/8279eb58886beb40eb19996ea7bec6d3610d64ea.textproto

@@ -0,0 +1,1092 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point1"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point1"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point1"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
+                      expression_pattern {
+                        expression {
+                          identifier {
+                            name: "Point1"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point1"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point1"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
+                    type {
+                      expression_pattern {
+                        expression {
+                          int_type_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point1"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point2"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point2"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point2"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
+                      expression_pattern {
+                        expression {
+                          identifier {
+                            name: "Point2"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point2"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                primitive_operator {
+                                  op: Add
+                                  arguments {
+                                    field_access {
+                                      field: "x"
+                                      aggregate {
+                                        identifier {
+                                          name: "me"
+                                        }
+                                      }
+                                    }
+                                  }
+                                  arguments {
+                                    field_access {
+                                      field: "x"
+                                      aggregate {
+                                        identifier {
+                                          name: "b"
+                                        }
+                                      }
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                int_literal {
+                                  value: 1
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                primitive_operator {
+                                  op: Add
+                                  arguments {
+                                    field_access {
+                                      field: "y"
+                                      aggregate {
+                                        identifier {
+                                          name: "me"
+                                        }
+                                      }
+                                    }
+                                  }
+                                  arguments {
+                                    field_access {
+                                      field: "y"
+                                      aggregate {
+                                        identifier {
+                                          name: "b"
+                                        }
+                                      }
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                int_literal {
+                                  value: 1
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point2"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
+                    type {
+                      expression_pattern {
+                        expression {
+                          int_type_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point2"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                primitive_operator {
+                                  op: Mul
+                                  arguments {
+                                    field_access {
+                                      field: "x"
+                                      aggregate {
+                                        identifier {
+                                          name: "me"
+                                        }
+                                      }
+                                    }
+                                  }
+                                  arguments {
+                                    identifier {
+                                      name: "v"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                int_literal {
+                                  value: 2
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                primitive_operator {
+                                  op: Mul
+                                  arguments {
+                                    field_access {
+                                      field: "y"
+                                      aggregate {
+                                        identifier {
+                                          name: "me"
+                                        }
+                                      }
+                                    }
+                                  }
+                                  arguments {
+                                    identifier {
+                                      name: "v"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                int_literal {
+                                  value: 2
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "ScaleGeneric"
+      deduced_parameters {
+        name: "U"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "c"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "U"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "U"
+          }
+        }
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+      }
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+        statements {
+          return_statement {
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+                        name: "ScaleGeneric"
+                      }
+                    }
+                    argument {
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+                                aggregate {
+                                  identifier {
+                                    name: "a"
+                                  }
+                                }
+                              }
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+                                fields {
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+                      identifier {
+                        name: "ScaleGeneric"
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+                    argument {
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+                                field: "Add"
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+                                    name: "b"
+                                  }
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+                              }
+                            }
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+                                fields {
+                                  identifier {
+                                    name: "b"
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+                          identifier {
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+                          }
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+                      }
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+                }
+              }
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+        }
+      }
+    }
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+      param_pattern {
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+      return_term {
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+          int_type_literal {
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+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
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+                argument {
+                  tuple_literal {
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+                      identifier {
+                        name: "a"
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+                    fields {
+                      int_literal {
+                        value: 5
+                      }
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+                  }
+                }
+              }
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+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
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+                arguments {
+                  primitive_operator {
+                    op: Sub
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+                      field_access {
+                        field: "x"
+                        aggregate {
+                          identifier {
+                            name: "q"
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+                    arguments {
+                      field_access {
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+                        aggregate {
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+                  int_literal {
+                    value: 40
+                  }
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+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/94de30bf12fefffb83c6912020ccd79db9b75824.textproto

@@ -0,0 +1,758 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
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+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
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+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
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+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
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+        variable {
+          binding {
+            name: "y"
+            type {
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+                expression {
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+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              type_type_literal {
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        call {
+          function {
+            identifier {
+              name: "Point"
+            }
+          }
+          argument {
+            tuple_literal {
+              fields {
+                int_type_literal {
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+          }
+        }
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+      interface {
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+          name: "Vector"
+        }
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+      members {
+        function {
+          name: "Zero"
+          param_pattern {
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+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
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+                argument {
+                  tuple_literal {
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+                      int_type_literal {
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+          body {
+            statements {
+              return_statement {
+                expression {
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+                    fields {
+                      name: "x"
+                      expression {
+                        int_literal {
+                          value: 0
+                        }
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+                    fields {
+                      name: "y"
+                      expression {
+                        int_literal {
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+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
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+              expression_pattern {
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+                      identifier {
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+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
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+                          }
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+                }
+              }
+            }
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+          return_term {
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+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
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+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
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+                      expression {
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+                          arguments {
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+                              field: "x"
+                              aggregate {
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+                                  name: "me"
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+                              field: "x"
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+                                  name: "b"
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+                      expression {
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+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
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+                          arguments {
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+                              aggregate {
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+                    }
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+      }
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+        function {
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+          me_pattern {
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+                expression {
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+                      identifier {
+                        name: "Point"
+                      }
+                    }
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+                          int_type_literal {
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+                    }
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+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
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+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
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+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
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+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        primitive_operator {
+                          op: Mul
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            identifier {
+                              name: "v"
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        primitive_operator {
+                          op: Mul
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            identifier {
+                              name: "v"
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
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+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
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+          binding_pattern {
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+            type {
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+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
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+              expression_pattern {
+                expression {
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+              }
+            }
+          }
+        }
+      }
+      return_term {
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+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
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+              call {
+                function {
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+                    field: "Scale"
+                    aggregate {
+                      call {
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+                                name: "a"
+                              }
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+                                    field: "Zero"
+                                    aggregate {
+                                      identifier {
+                                        name: "T"
+                                      }
+                                    }
+                                  }
+                                }
+                                argument {
+                                  tuple_literal {
+                                  }
+                                }
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+                }
+                argument {
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+                      identifier {
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+                }
+              }
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+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
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+      }
+      body {
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+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
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+                  expression {
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+                      value: 2
+                    }
+                  }
+                }
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+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
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+                              int_type_literal {
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
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+                }
+              }
+            }
+          }
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+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
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+                  int_literal {
+                    value: 10
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/9627133891194d30a116e7e183d4a9e40eff236c.textproto

@@ -0,0 +1,491 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        function {
+          name: "Origin"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "T"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "T"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              identifier {
+                name: "Number"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  primitive_operator {
+                    op: Add
+                    arguments {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                    arguments {
+                      identifier {
+                        name: "other"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "SumXY"
+      deduced_parameters {
+        name: "U"
+        type {
+          identifier {
+            name: "Number"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "p"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "U"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "U"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "Add"
+                    aggregate {
+                      field_access {
+                        field: "x"
+                        aggregate {
+                          call {
+                            function {
+                              field_access {
+                                field: "Origin"
+                                aggregate {
+                                  identifier {
+                                    name: "p"
+                                  }
+                                }
+                              }
+                            }
+                            argument {
+                              tuple_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      field_access {
+                        field: "y"
+                        aggregate {
+                          identifier {
+                            name: "p"
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+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 0
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 0
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "SumXY"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/97a085b3b3c6067c5ea0429ba5d2557a11945696.textproto

@@ -0,0 +1,661 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        identifier {
+          name: "Point"
+        }
+      }
+      interface {
+        identifier {
+          name: "Vector"
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        primitive_operator {
+                          op: Add
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
+                                identifier {
+                                  name: "b"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        primitive_operator {
+                          op: Add
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "b"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        primitive_operator {
+                          op: Mul
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            identifier {
+                              name: "v"
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        primitive_operator {
+                          op: Mul
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            identifier {
+                              name: "v"
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "a"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "b"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "m"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Add"
+                aggregate {
+                  identifier {
+                    name: "a"
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "n"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Scale"
+                aggregate {
+                  call {
+                    function {
+                      identifier {
+                        name: "m"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "b"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "n"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "s"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 4
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 3
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "b"
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 15
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/a9e58d564dc49ae2b671e69157f8deb371ed05aa.textproto

@@ -0,0 +1,281 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        function {
+          name: "Origin"
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "zero"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        identifier {
+                          name: "zero"
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        identifier {
+                          name: "zero"
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "GetX"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "T"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "T"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              type_type_literal {
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Origin"
+                    aggregate {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
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+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      int_literal {
+                        value: 0
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "GetX"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/b3b34df9065050aedbd5cd3f87aa5270f8562778.textproto

@@ -0,0 +1,580 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        function {
+          name: "Origin"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "T"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "T"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Clone"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "T"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        field_access {
+                          field: "x"
+                          aggregate {
+                            identifier {
+                              name: "me"
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        field_access {
+                          field: "y"
+                          aggregate {
+                            identifier {
+                              name: "me"
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "SumXY"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "T"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "T"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  call {
+                    function {
+                      field_access {
+                        field: "Add"
+                        aggregate {
+                          field_access {
+                            field: "x"
+                            aggregate {
+                              identifier {
+                                name: "me"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          field_access {
+                            field: "y"
+                            aggregate {
+                              identifier {
+                                name: "me"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              identifier {
+                name: "Number"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  primitive_operator {
+                    op: Add
+                    arguments {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                    arguments {
+                      identifier {
+                        name: "other"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Origin"
+                    aggregate {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "SumXY"
+                    aggregate {
+                      call {
+                        function {
+                          field_access {
+                            field: "Clone"
+                            aggregate {
+                              identifier {
+                                name: "p"
+                              }
+                            }
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/b457071ed35b662d1c8bff74a3396e5718b370f6.textproto

@@ -0,0 +1,255 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        function {
+          name: "Origin"
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "zero"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        identifier {
+                          name: "zero"
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        identifier {
+                          name: "zero"
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "GetX"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "T"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
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+            }
+          }
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+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
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+                              int_type_literal {
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+                            }
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Origin"
+                    aggregate {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
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+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      int_literal {
+                        value: 0
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "GetX"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/b6ca27aa9276f7a23bdf2a6a0a94f6f4798b1c3c.textproto

@@ -0,0 +1,201 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "x"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              int_literal {
+                value: 5
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "x"
+              }
+            }
+            rhs {
+              int_literal {
+                value: 10
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      primitive_operator {
+                        op: Ptr
+                        arguments {
+                          int_type_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              primitive_operator {
+                op: AddressOf
+                arguments {
+                  identifier {
+                    name: "x"
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              primitive_operator {
+                op: Deref
+                arguments {
+                  identifier {
+                    name: "p"
+                  }
+                }
+              }
+            }
+            rhs {
+              int_literal {
+                value: 7
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "q"
+                type {
+                  expression_pattern {
+                    expression {
+                      primitive_operator {
+                        op: Ptr
+                        arguments {
+                          int_type_literal {
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              primitive_operator {
+                op: AddressOf
+                arguments {
+                  primitive_operator {
+                    op: Deref
+                    arguments {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              primitive_operator {
+                op: Deref
+                arguments {
+                  identifier {
+                    name: "q"
+                  }
+                }
+              }
+            }
+            rhs {
+              int_literal {
+                value: 0
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "y"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              primitive_operator {
+                op: Deref
+                arguments {
+                  identifier {
+                    name: "p"
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              identifier {
+                name: "y"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/bbf51fb6519d507da617e8ad2f7aa820354ca2f4.textproto

@@ -0,0 +1,563 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        function {
+          name: "Origin"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "T"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "T"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
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+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "T"
+                                }
+                              }
+                            }
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+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "SumXY"
+          param_pattern {
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+                name: "p"
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+                            fields {
+                              identifier {
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+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "T"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  call {
+                    function {
+                      field_access {
+                        field: "Add"
+                        aggregate {
+                          field_access {
+                            field: "x"
+                            aggregate {
+                              identifier {
+                                name: "p"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
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+                      tuple_literal {
+                        fields {
+                          field_access {
+                            field: "y"
+                            aggregate {
+                              identifier {
+                                name: "p"
+                              }
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+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "SumFn"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              function_type {
+                parameter {
+                  tuple_literal {
+                    fields {
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+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              identifier {
+                                name: "T"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                return_type {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  field_access {
+                    field: "SumXY"
+                    aggregate {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              identifier {
+                                name: "T"
+                              }
+                            }
+                          }
+                        }
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+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
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+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              identifier {
+                name: "Number"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
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+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
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+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  primitive_operator {
+                    op: Add
+                    arguments {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                    arguments {
+                      identifier {
+                        name: "other"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
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+        }
+      }
+      body {
+        statements {
+          variable_definition {
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+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
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+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Origin"
+                    aggregate {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  call {
+                    function {
+                      field_access {
+                        field: "SumFn"
+                        aggregate {
+                          identifier {
+                            name: "p"
+                          }
+                        }
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/c120e8bd92006d2aae26bbb3086a990327e50cd6.textproto

@@ -0,0 +1,661 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        identifier {
+          name: "Point"
+        }
+      }
+      interface {
+        identifier {
+          name: "Vector"
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Point"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        primitive_operator {
+                          op: Add
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
+                                identifier {
+                                  name: "b"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        primitive_operator {
+                          op: Add
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
+                                identifier {
+                                  name: "b"
+                                }
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+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
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+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
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+                    }
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+                }
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+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Point"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        primitive_operator {
+                          op: Mul
+                          arguments {
+                            field_access {
+                              field: "x"
+                              aggregate {
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+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            identifier {
+                              name: "v"
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        primitive_operator {
+                          op: Mul
+                          arguments {
+                            field_access {
+                              field: "y"
+                              aggregate {
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+                                  name: "me"
+                                }
+                              }
+                            }
+                          }
+                          arguments {
+                            identifier {
+                              name: "v"
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "a"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "b"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
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+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
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+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "m"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
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+                field: "Add"
+                aggregate {
+                  identifier {
+                    name: "a"
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "n"
+                type {
+                  auto_pattern {
+                  }
+                }
+              }
+            }
+            init {
+              field_access {
+                field: "Scale"
+                aggregate {
+                  call {
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+                      identifier {
+                        name: "m"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "b"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "n"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "s"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
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+                  name: "x"
+                  expression {
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+                      value: 1
+                    }
+                  }
+                }
+                fields {
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+                  expression {
+                    int_literal {
+                      value: 4
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
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+                      value: 2
+                    }
+                  }
+                }
+                fields {
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+                  expression {
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+                      value: 3
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "b"
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 15
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/d191fc4462a50c502d790d51fd58e68346dc1505.textproto

@@ -0,0 +1,208 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    function {
+      name: "apply"
+      deduced_parameters {
+        name: "T"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+      deduced_parameters {
+        name: "U"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "f"
+            type {
+              expression_pattern {
+                expression {
+                  function_type {
+                    parameter {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "T"
+                          }
+                        }
+                      }
+                    }
+                    return_type {
+                      identifier {
+                        name: "U"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "U"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "f"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "x"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "positive"
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  bool_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          if_statement {
+            condition {
+              identifier {
+                name: "x"
+              }
+            }
+            then_block {
+              statements {
+                return_statement {
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+              }
+            }
+            else_block {
+              statements {
+                return_statement {
+                  expression {
+                    primitive_operator {
+                      op: Neg
+                      arguments {
+                        int_literal {
+                          value: 2
+                        }
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+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "apply"
+                  }
+                }
+                argument {
+                  tuple_literal {
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+                      identifier {
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+                      }
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+                      }
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+                }
+              }
+            }
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+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/d662ef1928345fc77bfd7993cc86eaf4e0ac1f07.textproto

@@ -0,0 +1,637 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
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+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
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+                  identifier {
+                    name: "Self"
+                  }
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+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
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+                  }
+                }
+              }
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+          return_term {
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+              identifier {
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+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
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+              binding_pattern {
+                name: "v"
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+              }
+            }
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+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
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+                }
+              }
+            }
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+        }
+      }
+      members {
+        variable {
+          binding {
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+            type {
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+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Self"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Zero"
+              param_pattern {
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            int_literal {
+                              value: 0
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            int_literal {
+                              value: 0
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
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+                  binding_pattern {
+                    name: "b"
+                    type {
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+                          identifier {
+                            name: "Self"
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+                }
+              }
+              return_term {
+                kind: Expression
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+                    name: "Self"
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+              }
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+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
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+                                  aggregate {
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+                                      name: "me"
+                                    }
+                                  }
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+                              }
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
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+              return_term {
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+                    name: "Self"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "a"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
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+            }
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+        }
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+      return_term {
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+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "Scale"
+                    aggregate {
+                      call {
+                        function {
+                          field_access {
+                            field: "Add"
+                            aggregate {
+                              identifier {
+                                name: "a"
+                              }
+                            }
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              call {
+                                function {
+                                  field_access {
+                                    field: "Zero"
+                                    aggregate {
+                                      identifier {
+                                        name: "T"
+                                      }
+                                    }
+                                  }
+                                }
+                                argument {
+                                  tuple_literal {
+                                  }
+                                }
+                              }
+                            }
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+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
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+                        name: "s"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
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+      param_pattern {
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+      return_term {
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+        type {
+          int_type_literal {
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+        }
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+      body {
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+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  int_literal {
+                    value: 10
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/e2abc580234fe84070585fa7f5a82679f2960ae1.textproto

@@ -0,0 +1,198 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        function {
+          name: "Origin"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Point"
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        int_literal {
+                          value: 0
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        int_literal {
+                          value: 0
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "GetX"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Point"
+                  }
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+              }
+            }
+          }
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "me"
+                      }
+                    }
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+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
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+            type {
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+                }
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+            }
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+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
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+      body {
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+          variable_definition {
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+                name: "p"
+                type {
+                  expression_pattern {
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+                        name: "Point"
+                      }
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+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Origin"
+                    aggregate {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+                argument {
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+                  }
+                }
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+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "GetX"
+                    aggregate {
+                      identifier {
+                        name: "p"
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+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/e36d2a76c57c42b04e5addbfddcad903420cf01e.textproto

@@ -0,0 +1,610 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
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+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
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+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
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+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
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+                name: "Number"
+              }
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+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Origin"
+      deduced_parameters {
+        name: "U"
+        type {
+          identifier {
+            name: "Number"
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+      }
+      param_pattern {
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+        type {
+          call {
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+              identifier {
+                name: "Point"
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+          return_statement {
+            expression {
+              struct_literal {
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+                  expression {
+                    call {
+                      function {
+                        field_access {
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+                          aggregate {
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+        type {
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+            name: "Number"
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+        type {
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+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              struct_literal {
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+                  expression {
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+                      aggregate {
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+                }
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+      }
+    }
+  }
+  declarations {
+    function {
+      name: "SumXY"
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+        name: "U"
+        type {
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+            name: "Number"
+          }
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+      }
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+                          identifier {
+                            name: "U"
+                          }
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "U"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "Add"
+                    aggregate {
+                      field_access {
+                        field: "x"
+                        aggregate {
+                          identifier {
+                            name: "other"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
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+                  tuple_literal {
+                    fields {
+                      field_access {
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+                            name: "other"
+                          }
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
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+                }
+              }
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+          param_pattern {
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+              binding_pattern {
+                name: "other"
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+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
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+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  primitive_operator {
+                    op: Add
+                    arguments {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                    arguments {
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
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+    }
+  }
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+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
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+                        function {
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+                            name: "Point"
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+                        argument {
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+                              int_type_literal {
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "Origin"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      int_literal {
+                        value: 0
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  identifier {
+                    name: "SumXY"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      call {
+                        function {
+                          identifier {
+                            name: "Clone"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              identifier {
+                                name: "p"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/e91903b4cd4a6d12e588185107239bb278cc8bfd.textproto

@@ -0,0 +1,704 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Vector"
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "b"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Scale"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "v"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        impl {
+          kind: InternalImpl
+          impl_type {
+            identifier {
+              name: "Point"
+            }
+          }
+          interface {
+            identifier {
+              name: "Vector"
+            }
+          }
+          members {
+            function {
+              name: "Add"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "b"
+                    type {
+                      expression_pattern {
+                        expression {
+                          identifier {
+                            name: "Point"
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+                      }
+                    }
+                  }
+                }
+              }
+              return_term {
+                kind: Expression
+                type {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
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+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
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+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
+                              op: Add
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "b"
+                                    }
+                                  }
+                                }
+                              }
+                            }
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+                      }
+                    }
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+                }
+              }
+            }
+          }
+          members {
+            function {
+              name: "Scale"
+              me_pattern {
+                name: "me"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+              param_pattern {
+                fields {
+                  binding_pattern {
+                    name: "v"
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+              }
+              return_term {
+                kind: Expression
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+                  identifier {
+                    name: "Point"
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+              }
+              body {
+                statements {
+                  return_statement {
+                    expression {
+                      struct_literal {
+                        fields {
+                          name: "x"
+                          expression {
+                            primitive_operator {
+                              op: Mul
+                              arguments {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
+                              }
+                            }
+                          }
+                        }
+                        fields {
+                          name: "y"
+                          expression {
+                            primitive_operator {
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+                              arguments {
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+                                  aggregate {
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+                                    }
+                                  }
+                                }
+                              }
+                              arguments {
+                                identifier {
+                                  name: "v"
+                                }
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+                          }
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "ScaleGeneric"
+      deduced_parameters {
+        name: "U"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
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+          binding_pattern {
+            name: "c"
+            type {
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+                  identifier {
+                    name: "U"
+                  }
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+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "s"
+            type {
+              expression_pattern {
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+              }
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+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "U"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
+              call {
+                function {
+                  field_access {
+                    field: "Scale"
+                    aggregate {
+                      identifier {
+                        name: "c"
+                      }
+                    }
+                  }
+                }
+                argument {
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+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "AddAndScaleGeneric"
+      deduced_parameters {
+        name: "T"
+        type {
+          identifier {
+            name: "Vector"
+          }
+        }
+      }
+      param_pattern {
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+            type {
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+            }
+          }
+        }
+        fields {
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+            }
+          }
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+            type {
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+        }
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+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "T"
+          }
+        }
+      }
+      body {
+        statements {
+          return_statement {
+            expression {
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+                  identifier {
+                    name: "ScaleGeneric"
+                  }
+                }
+                argument {
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+                      call {
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+                          field_access {
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+                            aggregate {
+                              identifier {
+                                name: "a"
+                              }
+                            }
+                          }
+                        }
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+                            fields {
+                              identifier {
+                                name: "b"
+                              }
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+                      identifier {
+                        name: "s"
+                      }
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+                  }
+                }
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+          }
+        }
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+  declarations {
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+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
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+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "a"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
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+                }
+              }
+            }
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+                  name: "x"
+                  expression {
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+                      value: 1
+                    }
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+                fields {
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+                  expression {
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+                      value: 1
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "b"
+                type {
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+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
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+                  expression {
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+                      value: 3
+                    }
+                  }
+                }
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+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
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+                function {
+                  identifier {
+                    name: "AddAndScaleGeneric"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "a"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "b"
+                      }
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+                    fields {
+                      int_literal {
+                        value: 5
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
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+                      }
+                    }
+                  }
+                }
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+                    value: 15
+                  }
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+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}

explorer/fuzzing/fuzzer_corpus/f798f9cb9e39bf2178f86cf24d17c4cc5583fd81.textproto

@@ -0,0 +1,851 @@
+compilation_unit {
+  package_statement {
+    package_name: "ExplorerTest"
+  }
+  is_api: true
+  declarations {
+    interface {
+      name: "Number"
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "Self"
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "Self"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              identifier {
+                name: "Self"
+              }
+            }
+          }
+        }
+      }
+      self {
+        name: "Self"
+        type {
+          type_type_literal {
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    class_declaration {
+      name: "Point"
+      members {
+        variable {
+          binding {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        variable {
+          binding {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "T"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      type_params {
+        fields {
+          generic_binding {
+            name: "T"
+            type {
+              identifier {
+                name: "Number"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        int_type_literal {
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  int_literal {
+                    value: 0
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  int_type_literal {
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      int_type_literal {
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              int_type_literal {
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  primitive_operator {
+                    op: Add
+                    arguments {
+                      identifier {
+                        name: "me"
+                      }
+                    }
+                    arguments {
+                      identifier {
+                        name: "other"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    impl {
+      kind: ExternalImpl
+      impl_type {
+        call {
+          function {
+            identifier {
+              name: "Point"
+            }
+          }
+          argument {
+            tuple_literal {
+              fields {
+                identifier {
+                  name: "U"
+                }
+              }
+            }
+          }
+        }
+      }
+      interface {
+        identifier {
+          name: "Number"
+        }
+      }
+      members {
+        function {
+          name: "Zero"
+          param_pattern {
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
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+                      identifier {
+                        name: "U"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "U"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Zero"
+                              aggregate {
+                                identifier {
+                                  name: "U"
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      members {
+        function {
+          name: "Add"
+          me_pattern {
+            name: "me"
+            type {
+              expression_pattern {
+                expression {
+                  call {
+                    function {
+                      identifier {
+                        name: "Point"
+                      }
+                    }
+                    argument {
+                      tuple_literal {
+                        fields {
+                          identifier {
+                            name: "U"
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          param_pattern {
+            fields {
+              binding_pattern {
+                name: "other"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              identifier {
+                                name: "U"
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          return_term {
+            kind: Expression
+            type {
+              call {
+                function {
+                  identifier {
+                    name: "Point"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "U"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+          body {
+            statements {
+              return_statement {
+                expression {
+                  struct_literal {
+                    fields {
+                      name: "x"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Add"
+                              aggregate {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                              fields {
+                                field_access {
+                                  field: "x"
+                                  aggregate {
+                                    identifier {
+                                      name: "other"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                    fields {
+                      name: "y"
+                      expression {
+                        call {
+                          function {
+                            field_access {
+                              field: "Add"
+                              aggregate {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "me"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                          argument {
+                            tuple_literal {
+                              fields {
+                                field_access {
+                                  field: "y"
+                                  aggregate {
+                                    identifier {
+                                      name: "other"
+                                    }
+                                  }
+                                }
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Sum"
+      deduced_parameters {
+        name: "E"
+        type {
+          identifier {
+            name: "Number"
+          }
+        }
+      }
+      param_pattern {
+        fields {
+          binding_pattern {
+            name: "x"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "E"
+                  }
+                }
+              }
+            }
+          }
+        }
+        fields {
+          binding_pattern {
+            name: "y"
+            type {
+              expression_pattern {
+                expression {
+                  identifier {
+                    name: "E"
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+      return_term {
+        kind: Expression
+        type {
+          identifier {
+            name: "E"
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "total"
+                type {
+                  expression_pattern {
+                    expression {
+                      identifier {
+                        name: "E"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  field_access {
+                    field: "Zero"
+                    aggregate {
+                      identifier {
+                        name: "E"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "total"
+              }
+            }
+            rhs {
+              call {
+                function {
+                  field_access {
+                    field: "Add"
+                    aggregate {
+                      identifier {
+                        name: "total"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "x"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          assign {
+            lhs {
+              identifier {
+                name: "total"
+              }
+            }
+            rhs {
+              call {
+                function {
+                  field_access {
+                    field: "Add"
+                    aggregate {
+                      identifier {
+                        name: "total"
+                      }
+                    }
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "y"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              identifier {
+                name: "total"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+  declarations {
+    function {
+      name: "Main"
+      param_pattern {
+      }
+      return_term {
+        kind: Expression
+        type {
+          int_type_literal {
+          }
+        }
+      }
+      body {
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "p"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 1
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 2
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "q"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              struct_literal {
+                fields {
+                  name: "x"
+                  expression {
+                    int_literal {
+                      value: 4
+                    }
+                  }
+                }
+                fields {
+                  name: "y"
+                  expression {
+                    int_literal {
+                      value: 3
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          variable_definition {
+            pattern {
+              binding_pattern {
+                name: "r"
+                type {
+                  expression_pattern {
+                    expression {
+                      call {
+                        function {
+                          identifier {
+                            name: "Point"
+                          }
+                        }
+                        argument {
+                          tuple_literal {
+                            fields {
+                              int_type_literal {
+                              }
+                            }
+                          }
+                        }
+                      }
+                    }
+                  }
+                }
+              }
+            }
+            init {
+              call {
+                function {
+                  identifier {
+                    name: "Sum"
+                  }
+                }
+                argument {
+                  tuple_literal {
+                    fields {
+                      identifier {
+                        name: "p"
+                      }
+                    }
+                    fields {
+                      identifier {
+                        name: "q"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+        statements {
+          return_statement {
+            expression {
+              primitive_operator {
+                op: Sub
+                arguments {
+                  field_access {
+                    field: "x"
+                    aggregate {
+                      identifier {
+                        name: "r"
+                      }
+                    }
+                  }
+                }
+                arguments {
+                  field_access {
+                    field: "y"
+                    aggregate {
+                      identifier {
+                        name: "r"
+                      }
+                    }
+                  }
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}