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// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-elem-put-obj-literal-prop-ref-init.case
// - src/dstr-assignment/default/for-of.template
/*---
description: The DestructuringAssignmentTarget of an AssignmentElement can extend to LHSExpressions if it is neither an ObjectLiteral nor an ArrayLiteral and its AssignmentTargetTyp is simple. Using MemberExpression (ObjLiteral + identifier) with initializer. (For..of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [destructuring-binding]
flags: [generated]
info: |
IterationStatement :
for ( LeftHandSideExpression of AssignmentExpression ) Statement
1. Let keyResult be the result of performing ? ForIn/OfHeadEvaluation(« »,
AssignmentExpression, iterate).
2. Return ? ForIn/OfBodyEvaluation(LeftHandSideExpression, Statement,
keyResult, assignment, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
4. If destructuring is true and if lhsKind is assignment, then
a. Assert: lhs is a LeftHandSideExpression.
b. Let assignmentPattern be the parse of the source text corresponding to
lhs using AssignmentPattern as the goal symbol.
[...]
Syntax
AssignmentPattern : ArrayAssignmentPattern
ArrayAssignmentPattern : [ AssignmentElementList ]
AssignmentElementList : AssignmentElisionElement
AssignmentElisionElement : Elision_opt AssignmentElement
AssignmentElement : DestructuringAssignmentTarget Initializer_opt
DestructuringAssignmentTarget : LeftHandSideExpression
Static Semantics: Early Errors
DestructuringAssignmentTarget : LeftHandSideExpression
- It is a Syntax Error if LeftHandSideExpression is either an ObjectLiteral or an ArrayLiteral and if LeftHandSideExpression is not covering an AssignmentPattern.
- It is a Syntax Error if LeftHandSideExpression is neither an ObjectLiteral nor an ArrayLiteral and AssignmentTargetType(LeftHandSideExpression) is not simple.
Runtime Semantics: DestructuringAssignmentEvaluation
ArrayAssignmentPattern : [ AssignmentElementList ]
1. Let iteratorRecord be ? GetIterator(value).
2. Let result be IteratorDestructuringAssignmentEvaluation of AssignmentElementList with argument iteratorRecord.
3. If iteratorRecord.[[Done]] is false, return ? IteratorClose(iteratorRecord, result).
4. Return result.
Runtime Semantics: IteratorDestructuringAssignmentEvaluation
AssignmentElement : DestructuringAssignmentTarget Initializer
1. If DestructuringAssignmentTarget is neither an ObjectLiteral nor an ArrayLiteral, then
a. Let lref be the result of evaluating DestructuringAssignmentTarget.
...
7. Return ? PutValue(lref, v).
---*/
var x, setValue;
var counter = 0;
for ([{
get y() {
throw new Test262Error('The property should not be accessed.');
},
set y(val) {
setValue = val;
}
}.y = 42] of [[23]]) {
assert.sameValue(setValue, 23);
counter += 1;
}
assert.sameValue(counter, 1);
reportCompare(0, 0);
|
