original_string: public function getOnce($key, $default = null)
      {
          $read = $this->get($key, $default);
          $this->delete($key);
          return $read;
      }
code: public function getOnce($key, $default = null)
      {
          $read = $this->get($key, $default);
          $this->delete($key);
          return $read;
      }
code_tokens: public function getOnce ( $ key , $ default = null ) { $ read = $ this -> get ( $ key , $ default ) ; $ this -> delete ( $ key ) ; return $ read ; }
docstring: Read a value from the session and unset it, this is a form of read
  once flash memory using the session.
  
  @param string $key     in session variable.
  @param mixed  $default default value to return when key is not set
  in the session.
  
  @return mixed value from session and null if not set.
docstring_tokens: Read a value from the session and unset it this is a form of read once flash memory using the session .