carbon-lang/executable_semantics/testdata/experimental_continuation/copy_in_continuation.carbon

// 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
//
// RUN: executable_semantics %s 2>&1 | \
// RUN:   FileCheck --match-full-lines --allow-unused-prefixes=false %s
// RUN: executable_semantics --trace %s 2>&1 | \
// RUN:   FileCheck --match-full-lines --allow-unused-prefixes %s
// AUTOUPDATE: executable_semantics %s
// CHECK: result: 3

package ExecutableSemanticsTest api;

// Test the way in which copying of continuations interacts with data
// on the stack such as the variable `x`. In this example the copy
// happens after the variable `x` is created.

var y: i32 = 0;

fn main() -> i32 {
  __continuation k1 {
    var x: i32 = 0;
    x = x + 1;
    __await;
    x = x + 2;
    y = x;
  }
  __run k1;
  var k2: __Continuation = k1;
  __run k2;
  return y;
}