odin-javascript-exercises/node_modules/lodash/keyBy.js

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2017-12-15 10:56:14 -08:00
var baseAssignValue = require('./_baseAssignValue'),
createAggregator = require('./_createAggregator');
/**
* Creates an object composed of keys generated from the results of running
* each element of `collection` thru `iteratee`. The corresponding value of
* each key is the last element responsible for generating the key. The
* iteratee is invoked with one argument: (value).
*
* @static
* @memberOf _
* @since 4.0.0
* @category Collection
* @param {Array|Object} collection The collection to iterate over.
* @param {Function} [iteratee=_.identity] The iteratee to transform keys.
* @returns {Object} Returns the composed aggregate object.
* @example
*
* var array = [
* { 'dir': 'left', 'code': 97 },
* { 'dir': 'right', 'code': 100 }
* ];
*
* _.keyBy(array, function(o) {
* return String.fromCharCode(o.code);
* });
* // => { 'a': { 'dir': 'left', 'code': 97 }, 'd': { 'dir': 'right', 'code': 100 } }
*
* _.keyBy(array, 'dir');
* // => { 'left': { 'dir': 'left', 'code': 97 }, 'right': { 'dir': 'right', 'code': 100 } }
*/
var keyBy = createAggregator(function(result, value, key) {
baseAssignValue(result, key, value);
});
module.exports = keyBy;