1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
|
// This file was procedurally generated from the following sources:
// - src/dstr-assignment/array-elem-nested-obj-yield-expr.case
// - src/dstr-assignment/default/for-of.template
/*---
description: When a `yield` token appears within the Initializer of a nested destructuring assignment and within a generator function body, it behaves as a YieldExpression. (For..of statement)
esid: sec-for-in-and-for-of-statements-runtime-semantics-labelledevaluation
features: [generators, 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.
[...]
---*/
var iterationResult, iter, x;
iter = (function*() {
var counter = 0;
for ([{ x = yield }] of [[{}]]) {
counter += 1;
}
assert.sameValue(counter, 1);
}());
iterationResult = iter.next();
assert.sameValue(iterationResult.value, undefined);
assert.sameValue(iterationResult.done, false);
assert.sameValue(x, undefined);
iterationResult = iter.next(4);
assert.sameValue(iterationResult.value, undefined);
assert.sameValue(iterationResult.done, true);
assert.sameValue(x, 4);
reportCompare(0, 0);
|
