* 判断数据类型是否为object * @param arg * @returns {boolean}

* Returns a random hexadecimal string

* Recursively clone native types.

* Safer Object.hasOwnProperty

* Pluralization helper.

* Similar to Array/forEach but works over object properties and fixes Don't * Enum bug on IE. * based on: http://whattheheadsaid.com/2010/10

* Combine properties from all the objects into first one. * - This method affects target object in place, if you want to create a new Object pass