Simple function to create secure inmutable (recursive deep copy) JavaScript Objects

deep-clone.js

  /**
   * Simple function to create secure inmutable (recursive deep copy) JavaScript Objects 
   * @license WTFPL
   * @param {Object/Array} obj Target Object. Required
   * @param {Number} depth Depth level. Defaults to 1
   * @return {Object/Array) Inmutable new Object
   * @method deepClone
   */
  function deepClone(obj, depth) {
    var clone, key,
        toStr = Object.prototype.toString;
    depth = depth || 1;
    if (typeof obj !== 'object' || obj === null) { return obj; }
    if (toStr.call(obj) === '[object String]') { return obj.splice(); }
    if (toStr.call(obj) === '[object Date]') { return new Date(obj.getTime()); }
    if (toStr.call(obj.clone) === '[object Function]') { return obj.clone(); }
    clone = toStr.call(obj) === '[object Array]' ? obj.slice() : (function(obj){ 
      var k, o = {};
      for (k in obj) { o[k] = obj[k]; }
      return o;
    }(obj));
    if (depth !== undefined && depth > 0) {
      for (key in clone) {
        clone[key] = deepClone(clone[key], depth-1);
      }
    }
    return clone;
  }