Language/12_Expressions/00_Object_Identity/1_Object_Identity_A02_t02.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 The predefined Dart function identical() is defined such that identical(c1, c2) iff:
 *   c1 and c2 are instances of double and one of the following holds:
 *      – c1 and c2 are non-zero and c1 == c2 .
 *      – Both c1 and c2 are +0.0.
 *      – Both c1 and c2 are −0.0.
 *      – Both c1 and c2 represent a NaN value.
 * @description Checks that two NaNs are identical.
 * @author kaigorodov
 * @reviewer rodionov
 * @needsreview issue 7024
 */
import "../../../Utils/expect.dart";

div(var a, var b) {
  return a/b;
}

var nol=0.0;

main() {
  double nan1=div(nol, nol);
  double nan2=div(nol, nol);
  Expect.isTrue(identical(nan1, nan2));
  Expect.isTrue(identical(nan1, double.NAN));
  Expect.isTrue(identical(double.NAN, double.NAN));
}