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// Copyright (C) 2016 the V8 project authors. All rights reserved.
// This code is governed by the BSD license found in the LICENSE file.
/*---
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
description: >
Creation of new lexical environment for the initial evaluation of the
statement body
info: |
IterationStatement : for ( ForDeclaration of AssignmentExpression ) Statement
[...]
2. Return ? ForIn/OfBodyEvaluation(ForDeclaration, Statement, keyResult,
lexicalBinding, labelSet).
13.7.5.13 Runtime Semantics: ForIn/OfBodyEvaluation
[...]
5. Repeat
[...]
d. If lhsKind is either assignment or varBinding, then
[...]
e. Else,
i. Assert: lhsKind is lexicalBinding.
ii. Assert: lhs is a ForDeclaration.
iii. Let iterationEnv be NewDeclarativeEnvironment(oldEnv).
iv. Perform BindingInstantiation for lhs passing iterationEnv as the
argument.
v. Set the running execution context's LexicalEnvironment to
iterationEnv.
[...]
features: [let]
---*/
var probeBefore = function() { return x; };
let x = 'outside';
var probeExpr, probeDecl, probeBody;
for (
let [x, _ = probeDecl = function() { return x; }]
in
{ i: probeExpr = function() { typeof x; }}
)
probeBody = function() { return x; };
assert.sameValue(probeBefore(), 'outside');
assert.throws(ReferenceError, probeExpr);
assert.sameValue(probeDecl(), 'i', 'reference from ForDeclaration');
assert.sameValue(probeBody(), 'i', 'reference from statement body');
reportCompare(0, 0);