Implementation of python's range() function in javascript.

range.js

/**
 * Range function, similar to python's one.
 * If you want to use it in for...in loops, all 4 arguments must be passed.
 * @param {Number} Start - If omited, it defaults to 0.
 * @param {Number} Stop
 * @param {Number} Step - If omited, it defaults to 1.
 * @param {Boolean} Object - If returns an object or not. Mostly used in for...in loops.
 * @return {Mixed} If Object is true, returns an object, otherwise, returns an array.
 * 
 * Examples:
 * >>> range(5)
 * [0, 1, 2, 3, 4]
 * >>> range(1, 6)
 * [1, 2, 3, 4, 5]
 * >>> range(0, 30, 5)
 * [0, 5, 10, 15, 20, 25]
 * >>> range(0, 4, 1, true)
 * {0:0, 1:1, 2:2, 3:3}
*/

function range(start, stop, step, object) {
  if (stop === undefined) {
    stop = start;
    start = 0;
  }

  if (step === undefined) {
    step = 1;
  }

  if ((step > 0 && start >= stop) || (step < 0 && start <= stop)) {
    return [];
  }

  var result = object ? new Object() : new Array();
  for (var i = start; step > 0 ? i < stop : i > stop; i += step) {
    object ? result[i] = i : result.push(i);
  }

  return result;
}