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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-runtime-semantics-evaluation
description: Value received from invocation of generator's `throw` method
info: |
YieldExpression : yield * AssignmentExpression
1. Let exprRef be the result of evaluating AssignmentExpression.
2. Let value be ? GetValue(exprRef).
3. Let iterator be ? GetIterator(value).
4. Let received be NormalCompletion(undefined).
5. Repeat
a. If received.[[Type]] is normal, then
[...]
b. Else if received.[[Type]] is throw, then
i. Let throw be ? GetMethod(iterator, "throw").
ii. If throw is not undefined, then
1. Let innerResult be ? Call(throw, iterator, « received.[[Value]]
»).
2. NOTE: Exceptions from the inner iterator throw method are
propagated. Normal completions from an inner throw method are
processed similarly to an inner next.
3. If Type(innerResult) is not Object, throw a TypeError exception.
4. Let done be ? IteratorComplete(innerResult).
5. If done is true, then
[...]
6. Let received be GeneratorYield(innerResult).
features: [generators, Symbol.iterator]
---*/
var quickIter = {};
var iter, exprValue, throwReceived;
quickIter[Symbol.iterator] = function() {
return {
next: function() {
return { done: false };
},
throw: function(x) {
throwReceived = x;
return { done: true, value: 3333 };
}
};
};
function* g() {
exprValue = yield * quickIter;
}
iter = g();
iter.next();
iter.throw(2222);
assert.sameValue(throwReceived, 2222);
assert.sameValue(exprValue, 3333);
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