N-Ary/Multiple-List Cartesian Product

cartesian-product.js

/* N-ary cartesian product.
 * Input: any number of lists
 * Output: the cartesian product of the above lists as list of lists
 * Example: cartesianProduct([1, 2], ['cat']) -> [ [1, 'cat'], [2, 'cat'] ]
 */
var cartesianProduct = function () {
  function addNextList (tuples, list) {
    var result = [];
    tuples.forEach(function (tuple) {
      list.forEach(function (item) {
        result.push(tuple.concat(item));
      });
    });
    return result;
  }

  var lists = Array.prototype.slice.call(arguments, 0);
  return lists.reduce(addNextList, [[]]);
};