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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elem-id-iter-val-array-prototype.case
// - src/dstr-binding/default/const-stmt.template
/*---
description: Array destructuring uses overriden Array.prototype[Symbol.iterator] (`const` statement)
esid: sec-let-and-const-declarations-runtime-semantics-evaluation
features: [Symbol.iterator, generators, destructuring-binding]
flags: [generated]
info: |
LexicalBinding : BindingPattern Initializer
1. Let rhs be the result of evaluating Initializer.
2. Let value be GetValue(rhs).
3. ReturnIfAbrupt(value).
4. Let env be the running execution context's LexicalEnvironment.
5. Return the result of performing BindingInitialization for BindingPattern
using value and env as the arguments.
Runtime Semantics: IteratorBindingInitialization
SingleNameBinding : BindingIdentifier Initializer_opt
1. Let bindingId be StringValue of BindingIdentifier.
2. Let lhs be ? ResolveBinding(bindingId, environment).
3. If iteratorRecord.[[Done]] is false, then
a. Let next be IteratorStep(iteratorRecord).
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).
[...]
7. Return InitializeReferencedBinding(lhs, v).
---*/
Array.prototype[Symbol.iterator] = function* () {
if (this.length > 0) {
yield this[0];
}
if (this.length > 1) {
yield this[1];
}
if (this.length > 2) {
yield 42;
}
};
const [x, y, z] = [1, 2, 3];
assert.sameValue(x, 1);
assert.sameValue(y, 2);
assert.sameValue(z, 42);
reportCompare(0, 0);
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