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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-rest-ary-elem.case
// - src/dstr-binding/default/for-of-let.template
/*---
description: Rest element containing an array BindingElementList pattern (for-of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
es6id: 13.7.5.11
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
BindingRestElement : ... BindingPattern
1. Let A be ArrayCreate(0).
[...]
3. Repeat
[...]
b. If iteratorRecord.[[done]] is true, then
i. Return the result of performing BindingInitialization of
BindingPattern with A and environment as the arguments.
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
SingleNameBinding : BindingIdentifier Initializeropt
[...]
4. If iteratorRecord.[[done]] is false, then
a. Let next be IteratorStep(iteratorRecord.[[iterator]]).
b. If next is an abrupt completion, set iteratorRecord.[[done]] to true.
c. ReturnIfAbrupt(next).
d. If next is false, set iteratorRecord.[[done]] to true.
e. Else,
[...]
i. Let v be IteratorValue(next).
ii. If v is an abrupt completion, set
iteratorRecord.[[done]] to true.
iii. ReturnIfAbrupt(v).
5. If iteratorRecord.[[done]] is true, let v be undefined.
[...]
8. Return InitializeReferencedBinding(lhs, v).
---*/
var iterCount = 0;
for (let [...[x, y, z]] of [[3, 4, 5]]) {
assert.sameValue(x, 3);
assert.sameValue(y, 4);
assert.sameValue(z, 5);
iterCount += 1;
}
assert.sameValue(iterCount, 1, 'Iteration occurred as expected');
|
