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/**
* Lo-Dash 2.4.1 (Custom Build) <http://lodash.com/>
* Build: `lodash modularize exports="node" -o ./compat/`
* Copyright 2012-2013 The Dojo Foundation <http://dojofoundation.org/>
* Based on Underscore.js 1.5.2 <http://underscorejs.org/LICENSE>
* Copyright 2009-2013 Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors
* Available under MIT license <http://lodash.com/license>
*/
var baseRandom = require('../internals/baseRandom'),
forEach = require('./forEach');
/**
* Creates an array of shuffled values, using a version of the Fisher-Yates
* shuffle. See http://en.wikipedia.org/wiki/Fisher-Yates_shuffle.
*
* @static
* @memberOf _
* @category Collections
* @param {Array|Object|string} collection The collection to shuffle.
* @returns {Array} Returns a new shuffled collection.
* @example
*
* _.shuffle([1, 2, 3, 4, 5, 6]);
* // => [4, 1, 6, 3, 5, 2]
*/
function shuffle(collection) {
var index = -1,
length = collection ? collection.length : 0,
result = Array(typeof length == 'number' ? length : 0);
forEach(collection, function(value) {
var rand = baseRandom(0, ++index);
result[index] = result[rand];
result[rand] = value;
});
return result;
}
module.exports = shuffle;