carbon-lang/executable_semantics/testdata/choice1.6c

// Part of the Carbon Language project, under the Apache License v2.0 with LLVM
// Exceptions. See /LICENSE for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

choice Ints {
  None,
  One(Int),
  Two(Int,Int)
}

fn main() -> Int {
  var auto x = Ints.None();
  var auto y = Ints.One(42);
  var auto n = 0;
  match (y) {
    case Ints.None =>
      n = n + 2;
    case Ints.One(auto x) =>
      n = x + 1 - 42;
    case Ints.Two(auto a, auto b) =>
      n = 2;
  }
  match (x) {
    case Ints.One(auto x) =>
      n = x + 2;
    case Ints.None() =>
      n = n - 1;
    case Ints.Two(auto x, auto y) =>
      n = 5;
  }
  return n;
}

// Test some alternate syntaxes
choice MoreInts {
  None(),
  One(Int),
  Two(Int,Int),
}