function gettype (mixed_var) {
  // http://kevin.vanzonneveld.net
  // +   original by: Paulo Freitas
  // +   improved by: Kevin van Zonneveld (http://kevin.vanzonneveld.net)
  // +   improved by: Douglas Crockford (http://javascript.crockford.com)
  // +   input by: KELAN
  // +   improved by: Brett Zamir (http://brett-zamir.me)
  // -    depends on: is_float
  // %        note 1: 1.0 is simplified to 1 before it can be accessed by the function, this makes
  // %        note 1: it different from the PHP implementation. We can't fix this unfortunately.
  // *     example 1: gettype(1);
  // *     returns 1: 'integer'
  // *     example 2: gettype(undefined);
  // *     returns 2: 'undefined'
  // *     example 3: gettype({0: 'Kevin van Zonneveld'});
  // *     returns 3: 'array'
  // *     example 4: gettype('foo');
  // *     returns 4: 'string'
  // *     example 5: gettype({0: function () {return false;}});
  // *     returns 5: 'array'
  var s = typeof mixed_var,
    name;
  var getFuncName = function (fn) {
    var name = (/\W*function\s+([\w\$]+)\s*\(/).exec(fn);
    if (!name) {
      return '(Anonymous)';
    }
    return name[1];
  };
  if (s === 'object') {
    if (mixed_var !== null) { // From: http://javascript.crockford.com/remedial.html
      if (typeof mixed_var.length === 'number' && !(mixed_var.propertyIsEnumerable('length')) && typeof mixed_var.splice === 'function') {
        s = 'array';
      } else if (mixed_var.constructor && getFuncName(mixed_var.constructor)) {
        name = getFuncName(mixed_var.constructor);
        if (name === 'Date') {
          s = 'date'; // not in PHP
        } else if (name === 'RegExp') {
          s = 'regexp'; // not in PHP
        } else if (name === 'PHPJS_Resource') { // Check against our own resource constructor
          s = 'resource';
        }
      }
    } else {
      s = 'null';
    }
  } else if (s === 'number') {
    s = this.is_float(mixed_var) ? 'double' : 'integer';
  }
  return s;
}

gettype(1);

'integer'

gettype(undefined);

'undefined'

gettype({0: 'Kevin van Zonneveld'});

'array'