34 lines
882 B
Plaintext
34 lines
882 B
Plaintext
|
/**
|
||
|
* Copyright (c) 2013-present, Facebook, Inc.
|
||
|
*
|
||
|
* This source code is licensed under the MIT license found in the
|
||
|
* LICENSE file in the root directory of this source tree.
|
||
|
*
|
||
|
* @providesModule flatMapArray
|
||
|
* @typechecks
|
||
|
*/
|
||
|
|
||
|
var push = Array.prototype.push;
|
||
|
|
||
|
/**
|
||
|
* Applies a function to every item in an array and concatenates the resulting
|
||
|
* arrays into a single flat array.
|
||
|
*
|
||
|
* @param {array} array
|
||
|
* @param {function} fn
|
||
|
* @return {array}
|
||
|
*/
|
||
|
function flatMapArray(array, fn) {
|
||
|
var ret = [];
|
||
|
for (var ii = 0; ii < array.length; ii++) {
|
||
|
var result = fn.call(array, array[ii], ii);
|
||
|
if (Array.isArray(result)) {
|
||
|
push.apply(ret, result);
|
||
|
} else if (result != null) {
|
||
|
throw new TypeError('flatMapArray: Callback must return an array or null, ' + 'received "' + result + '" instead');
|
||
|
}
|
||
|
}
|
||
|
return ret;
|
||
|
}
|
||
|
|
||
|
module.exports = flatMapArray;
|