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// This file was procedurally generated from the following sources:
// - src/dstr-binding/ary-ptrn-elision.case
// - src/dstr-binding/default/gen-func-decl.template
/*---
description: Elision advances iterator (generator function declaration)
esid: sec-generator-function-definitions-runtime-semantics-instantiatefunctionobject
features: [generators, destructuring-binding]
flags: [generated]
info: |
GeneratorDeclaration : function * ( FormalParameters ) { GeneratorBody }
[...]
2. Let F be GeneratorFunctionCreate(Normal, FormalParameters,
GeneratorBody, scope, strict).
[...]
9.2.1 [[Call]] ( thisArgument, argumentsList)
[...]
7. Let result be OrdinaryCallEvaluateBody(F, argumentsList).
[...]
9.2.1.3 OrdinaryCallEvaluateBody ( F, argumentsList )
1. Let status be FunctionDeclarationInstantiation(F, argumentsList).
[...]
9.2.12 FunctionDeclarationInstantiation(func, argumentsList)
[...]
23. Let iteratorRecord be Record {[[iterator]]:
CreateListIterator(argumentsList), [[done]]: false}.
24. If hasDuplicates is true, then
[...]
25. Else,
b. Let formalStatus be IteratorBindingInitialization for formals with
iteratorRecord and env as arguments.
[...]
13.3.3.6 Runtime Semantics: IteratorBindingInitialization
ArrayBindingPattern : [ Elision ]
1. Return the result of performing
IteratorDestructuringAssignmentEvaluation of Elision with iteratorRecord
as the argument.
12.14.5.3 Runtime Semantics: IteratorDestructuringAssignmentEvaluation
Elision : ,
1. If iteratorRecord.[[done]] is false, then
a. Let next be IteratorStep(iteratorRecord.[[iterator]]).
b. If next is an abrupt completion, set iteratorRecord.[[done]] to true.
c. ReturnIfAbrupt(next).
d. If next is false, set iteratorRecord.[[done]] to true.
2. Return NormalCompletion(empty).
---*/
var first = 0;
var second = 0;
function* g() {
first += 1;
yield;
second += 1;
};
var callCount = 0;
function* f([,]) {
assert.sameValue(first, 1);
assert.sameValue(second, 0);
callCount = callCount + 1;
};
f(g()).next();
assert.sameValue(callCount, 1, 'generator function invoked exactly once');
reportCompare(0, 0);
|
