Language/12_Expressions/19_Conditional_A02_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 a conditional expression c of the form e1 ? e2 : e3
 * proceeds as follows:
 * First, e1 is evaluated to an object o1. In checked mode, it is a dynamic
 * type error if o1 is not of type bool. Otherwise, o1 is then subjected to boolean
 * conversion producing an object r. If r is true, then the value of c is the
 * result of evaluating the expression e2. Otherwise the value of c is the result of
 * evaluating the expression e3.
 * @description Checks that a conditional expression is evaluated correctly.
 * @static-warning
 * @author msyabro
 * @reviewer kaigorodov
 */
import "../../Utils/expect.dart";
 
import "../../Utils/dynamic_check.dart";

main() {
  Expect.equals(1, true ? 1 : 2);
  Expect.equals(2, false ? 1: 2);

  Expect.equals("yes", (2 > 1) ? "yes" : "no");
  Expect.equals("no", (2 <= -2) ? "yes" : "no");
  Expect.equals("yes", (identical(0, 0)) ? "yes" : "no");

  //scripting mode only, raises static type warnings
  checkTypeError(() {
    Expect.equals(0, [] ? 1 : 0); /// static type warning - first argument not assignable to boolean, see "Conditional"
  });
  
  checkTypeError(() {
    Expect.equals(0, new Object() ? 1 : 0);
  });
  
  checkTypeError(() {
    Expect.equals(0, "" ? 1 : 0); /// static type warning - first argument not assignable to boolean, see "Conditional"
  });
}