code: public function has($name)
      {
          return isset($this->_cookies[$name]) && $this->_cookies[$name]->value !== ''
              && ($this->_cookies[$name]->expire === null || $this->_cookies[$name]->expire === 0 || $this->_cookies[$name]->expire >= time());
      }
docs: Returns whether there is a cookie with the specified name.
  Note that if a cookie is marked for deletion from browser, this method will return false.
  @param string $name the cookie name
  @return bool whether the named cookie exists
  @see remove()