old_contents: /**
   * @file 生成唯一id
   * @author errorrik(errorrik@gmail.com)
   */
  
  
  /**
   * 唯一id的起始值
   *
   * @inner
   * @type {number}
   */
  var guidIndex = 1;
  
  /**
   * 唯一id的前缀
   *
   * @inner
   * @type {string}
   */
  var guidPrefix = (new Date()).getTime().toString(16);
  
  /**
   * 获取唯一id
   *
   * @inner
   * @return {string} 唯一id
   */
  function guid() {
      return '_san_' + guidPrefix + (guidIndex++);
  }
  
  exports = module.exports = guid;
  
new_contents: /**
   * @file 生成唯一id
   * @author errorrik(errorrik@gmail.com)
   */
  
  
  /**
   * 唯一id的起始值
   *
   * @inner
   * @type {number}
   */
  var guidIndex = 1;
  
  /**
   * 唯一id的前缀
   *
   * @inner
   * @type {string}
   */
  var guidPrefix = (new Date()).getTime().toString(16).slice(7);
  
  /**
   * 获取唯一id
   *
   * @inner
   * @return {string} 唯一id
   */
  function guid() {
      return '_san_' + guidPrefix + (guidIndex++);
  }
  
  exports = module.exports = guid;
  
subject: make id prefix short