mout/array/pick.js

var randInt = require('../random/randInt');

    /**
     * Remove random item(s) from the Array and return it.
     * Returns an Array of items if [nItems] is provided or a single item if
     * it isn't specified.
     */
    function pick(arr, nItems){
        if (nItems != null) {
            var result = [];
            if (nItems > 0 && arr && arr.length) {
                nItems = nItems > arr.length? arr.length : nItems;
                while (nItems--) {
                    result.push( pickOne(arr) );
                }
            }
            return result;
        }
        return (arr && arr.length)? pickOne(arr) : void(0);
    }


    function pickOne(arr){
        var idx = randInt(0, arr.length - 1);
        return arr.splice(idx, 1)[0];
    }


    module.exports = pick;