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// |reftest| error:SyntaxError
// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-elem-nested-memberexpr-optchain-prop-ref-init.case
// - src/dstr-assignment/syntax/for-in.template
/*---
description: It is a Syntax Error if LeftHandSideExpression of an DestructuringAssignmentTarget is neither an ObjectLiteral nor an ArrayLiteral and AssignmentTargetType(LeftHandSideExpression) is not simple Using Object (MemberExpression OptionalChain .IdentifierName Initializer) (For..in statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [optional-chaining, destructuring-binding]
flags: [generated]
negative:
phase: parse
type: SyntaxError
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
AssignmentElement : DestructuringAssignmentTarget Initializer_opt
DestructuringAssignmentTarget : LeftHandSideExpression
Static Semantics: Early Errors
OptionalExpression:
MemberExpression OptionalChain
CallExpression OptionalChain
OptionalExpression OptionalChain
OptionalChain:
?. [ Expression ]
?. IdentifierName
?. Arguments
?. TemplateLiteral
OptionalChain [ Expression ]
OptionalChain .IdentifierName
OptionalChain Arguments
OptionalChain TemplateLiteral
DestructuringAssignmentTarget : LeftHandSideExpression
- It is a Syntax Error if LeftHandSideExpression is neither an ObjectLiteral nor an ArrayLiteral and IsValidSimpleAssignmentTarget(LeftHandSideExpression) is not true.
Static Semantics: IsValidSimpleAssignmentTarget
LeftHandSideExpression : OptionalExpression
1. Return false.
---*/
$DONOTEVALUATE();
var x = {};
for ([x?.y = 42] in [[23]]) ;