40 lines
1.1 KiB
JavaScript
40 lines
1.1 KiB
JavaScript
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/**
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* Copyright 2013-present, Facebook, Inc.
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* All rights reserved.
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*
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* This source code is licensed under the BSD-style license found in the
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* LICENSE file in the root directory of this source tree. An additional grant
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* of patent rights can be found in the PATENTS file in the same directory.
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*
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*
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*/
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'use strict';
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/* global Symbol */
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var ITERATOR_SYMBOL = typeof Symbol === 'function' && Symbol.iterator;
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var FAUX_ITERATOR_SYMBOL = '@@iterator'; // Before Symbol spec.
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/**
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* Returns the iterator method function contained on the iterable object.
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*
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* Be sure to invoke the function with the iterable as context:
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*
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* var iteratorFn = getIteratorFn(myIterable);
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* if (iteratorFn) {
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* var iterator = iteratorFn.call(myIterable);
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* ...
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* }
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*
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* @param {?object} maybeIterable
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* @return {?function}
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*/
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function getIteratorFn(maybeIterable) {
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var iteratorFn = maybeIterable && (ITERATOR_SYMBOL && maybeIterable[ITERATOR_SYMBOL] || maybeIterable[FAUX_ITERATOR_SYMBOL]);
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if (typeof iteratorFn === 'function') {
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return iteratorFn;
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}
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}
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module.exports = getIteratorFn;
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