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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-generator-function-definitions
es6id: 14.4
description: >
YieldExpression contextually recognizes the `in` keyword as part of a
RelationalExpression
info: |
Syntax
yield [no LineTerminator here] AssignmentExpression[?In, +Yield]
features: [generators, Symbol.iterator]
---*/
var obj = Object.create({ hit: true });
var iter, iterResult, value;
Boolean.prototype[Symbol.iterator] = function* () { yield this.valueOf(); };
function* g() {
value = yield * 'hit' in obj;
value = yield * 'miss' in obj;
}
iter = g();
iterResult = iter.next('first');
assert.sameValue(iterResult.done, false, '`done` property (first iteration)');
assert.sameValue(iterResult.value, true, '`value` property (first iteration)');
assert.sameValue(
value, undefined, 'generator paused prior to evaluating AssignmentExpression'
);
iterResult = iter.next('second');
assert.sameValue(iterResult.done, false, '`done` property (second iteration)');
assert.sameValue(
iterResult.value, false, '`value` property (second iteration)'
);
assert.sameValue(value, undefined, 'value of first AssignmentExpression');
iterResult = iter.next('third');
assert.sameValue(iterResult.done, true, '`done` property (third iteration)');
assert.sameValue(
iterResult.value, undefined, '`value` property (third iteration)'
);
assert.sameValue(value, undefined, 'value of second AssignmentExpression');
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