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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-init-skipped.case
// - src/dstr-binding/default/for-of-const.template
/*---
description: Destructuring initializer is not evaluated when value is not `undefined` (for-of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [destructuring-binding]
flags: [generated]
info: |
IterationStatement :
for ( ForDeclaration of AssignmentExpression ) Statement
[...]
3. Return ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult,
lexicalBinding, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
3. Let destructuring be IsDestructuring of lhs.
[...]
5. Repeat
[...]
h. If destructuring is false, then
[...]
i. Else
i. If lhsKind is assignment, then
[...]
ii. Else if lhsKind is varBinding, then
[...]
iii. Else,
1. Assert: lhsKind is lexicalBinding.
2. Assert: lhs is a ForDeclaration.
3. Let status be the result of performing BindingInitialization
for lhs passing nextValue and iterationEnv as arguments.
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
SingleNameBinding : BindingIdentifier Initializeropt
[...]
6. If Initializer is present and v is undefined, then
[...]
7. If environment is undefined, return PutValue(lhs, v).
8. Return InitializeReferencedBinding(lhs, v).
---*/
var initCount = 0;
function counter() {
initCount += 1;
}
var iterCount = 0;
for (const [w = counter(), x = counter(), y = counter(), z = counter()] of [[null, 0, false, '']]) {
assert.sameValue(w, null);
assert.sameValue(x, 0);
assert.sameValue(y, false);
assert.sameValue(z, '');
assert.sameValue(initCount, 0);
iterCount += 1;
}
assert.sameValue(iterCount, 1, 'iteration occurred as expected');
reportCompare(0, 0);
|
