1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
|
// Copyright (C) 2019 Leo Balter. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
description: >
CoalesceExpression is chainable with the BitwiseORExpression
esid: sec-conditional-operator
info: |
ConditionalExpression :
ShortCircuitExpression
ShortCircuitExpression ? AssignmentExpression : AssignmentExpression
ShortCircuitExpression :
LogicalORExpression
CoalesceExpression
CoalesceExpression :
CoalesceExpressionHead ?? BitwiseORExpression
CoalesceExpressionHead :
CoalesceExpression
BitwiseORExpression
Runtime Semantics: Evaluation
CoalesceExpression:CoalesceExpressionHead??BitwiseORExpression
1. Let lref be the result of evaluating CoalesceExpressionHead.
2. Let lval be ? GetValue(lref).
3. If lval is undefined or null,
a. Let rref be the result of evaluating BitwiseORExpression.
b. Return ? GetValue(rref).
4. Otherwise, return lval.
features: [coalesce-expression]
---*/
var x;
x = null ?? 1 | 42;
assert.sameValue(x, 43, 'null ?? 1 | 42');
x = undefined ?? 1 | 42;
assert.sameValue(x, 43, 'null ?? 1 | 42');
x = false ?? 1 | 42;
assert.sameValue(x, false, 'false ?? 1 | 42');
x = true ?? 1 | 42;
assert.sameValue(x, true, 'true ?? 1 | 42');
|
