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// 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 LogicalORExpression is any is covered.
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 = undefined;
x = (null ?? 42) || 43;
assert.sameValue(x, 42, '(null ?? 42) || 43');
x = undefined;
x = null ?? (42 || 43);
assert.sameValue(x, 42, 'null ?? (42 || 43)`');
x = undefined;
x = (null || 42) ?? 43;
assert.sameValue(x, 42, '(null || 42) ?? 43');
x = undefined;
x = null || (42 ?? 43);
assert.sameValue(x, 42, 'null || (42 ?? 43)`');
x = undefined;
x = (42 || 43) ?? null;
assert.sameValue(x, 42, '(42 || 43) ?? null');
x = undefined;
x = 42 || (null ?? 43);
assert.sameValue(x, 42, '42 || (null ?? 43)');
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