Language/Expressions/Function_Invocation/Actual_Argument_List_Evaluation/evaluation_order_t01.dart

// Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

/**
 * @assertion Evaluation of an actual argument list of the form
 * (a1, ..., am, q1: am+1, ..., ql: am+l) proceeds as follows:
 * The arguments a1, ..., am+l are evaluated in the order they appear in the
 * program, yielding objects o1, ..., om+l.
 * @description Checks that expressions in an argument list are evaluated in
 * the order of appearance, from left to right and separately from each other.
 * @author msyabro
 */
import '../../../../Utils/expect.dart';

late StringBuffer buffer;

func(p1, p2, {p3, p4}) {}

class A {
  operator +(otherOperand) {
    buffer.write("A");
  }
  operator -(otherOperand) {
    buffer.write("B");
  }
  operator *(otherOperand) {
    buffer.write("C");
  }
  operator /(otherOperand) {
    buffer.write("D");
  }
}

A foo() {
  return new A();
}

bar(x, y) {
  Expect.isFalse(identical(x, y));
}

main() {
  buffer = new StringBuffer();
  func(new A() + 1, new A() - 1, p4: new A() * 1, p3: new A() / 1);
  Expect.equals("ABCD", buffer.toString());

  // shuffle the named arguments
  buffer.clear();
  func(new A() + 1, new A() - 1, p3: new A() * 1, p4: new A() / 1);
  Expect.equals("ABCD", buffer.toString());

  bar(foo(), foo());
}