Files
react-native/Libraries/Renderer/src/shared/utils/getIteratorFn.js
T
David Aurelio 3683beb88a RN: Update React (2/2)
Reviewed By: kentaromiura

Differential Revision: D4026114

fbshipit-source-id: 67808af91454d95941fea01eef58a4d9086f46e1
2016-11-04 05:43:44 -07:00

44 lines
1.2 KiB
JavaScript

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