1// Copyright 2008 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28// const variables should be read-only
29const c = 42;
30c = 87;
31assertEquals(42, c);
32
33
34// const variables are not behaving like other JS variables when it comes
35// to scoping - in fact they behave more sanely. Inside a 'with' they do
36// not interfere with the 'with' scopes.
37
38(function () {
39  with ({ x: 42 }) {
40    const x = 7;
41  }
42  x = 5;
43  assertEquals(7, x);
44})();
45
46
47// const variables may be declared but never initialized, in which case
48// their value is undefined.
49
50(function (sel) {
51  if (sel == 0)
52    with ({ x: 42 }) {
53    const x;
54    }
55  else
56    x = 3;
57  x = 5;
58  assertTrue(typeof x == 'undefined');
59})(1);
60
61
62// const variables may be initialized to undefined.
63(function () {
64  with ({ x: 42 }) {
65    const x = undefined;
66  }
67  x = 5;
68  assertTrue(typeof x == 'undefined');
69})();
70
71
72// const variables may be accessed in inner scopes like any other variable.
73(function () {
74  function bar() {
75    assertEquals(7, x);
76  }
77  with ({ x: 42 }) {
78    const x = 7;
79  }
80  x = 5
81  bar();
82})();
83
84
85// const variables may be declared via 'eval'
86(function () {
87  with ({ x: 42 }) {
88    eval('const x = 7');
89  }
90  x = 5;
91  assertEquals(7, x);
92})();
93