define(['./_isArrayLike', './clone', './values', './_getLength', './random'], function (_isArrayLike, clone, values, _getLength, random) { // Sample **n** random values from a collection using the modern version of the // [Fisher-Yates shuffle](https://en.wikipedia.org/wiki/Fisher–Yates_shuffle). // If **n** is not specified, returns a single random element. // The internal `guard` argument allows it to work with `_.map`. function sample(obj, n, guard) { if (n == null || guard) { if (!_isArrayLike(obj)) obj = values(obj); return obj[random(obj.length - 1)]; } var sample = _isArrayLike(obj) ? clone(obj) : values(obj); var length = _getLength(sample); n = Math.max(Math.min(n, length), 0); var last = length - 1; for (var index = 0; index < n; index++) { var rand = random(index, last); var temp = sample[index]; sample[index] = sample[rand]; sample[rand] = temp; } return sample.slice(0, n); } return sample; });