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1import createAggregator from './_createAggregator';
2
3/**
4 * Creates an object composed of keys generated from the results of running
5 * each element of `collection` thru `iteratee`. The corresponding value of
6 * each key is the last element responsible for generating the key. The
7 * iteratee is invoked with one argument: (value).
8 *
9 * @static
10 * @memberOf _
11 * @since 4.0.0
12 * @category Collection
13 * @param {Array|Object} collection The collection to iterate over.
14 * @param {Array|Function|Object|string} [iteratee=_.identity]
15 * The iteratee to transform keys.
16 * @returns {Object} Returns the composed aggregate object.
17 * @example
18 *
19 * var array = [
20 * { 'dir': 'left', 'code': 97 },
21 * { 'dir': 'right', 'code': 100 }
22 * ];
23 *
24 * _.keyBy(array, function(o) {
25 * return String.fromCharCode(o.code);
26 * });
27 * // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
28 *
29 * _.keyBy(array, 'dir');
30 * // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
31 */
32var keyBy = createAggregator(function(result, value, key) {
33 result[key] = value;
34});
35
36export default keyBy;