original_string: public function add($middleware)
      {
          if (is_array($middleware)) {
              $this->queue = array_merge($this->queue, $middleware);
  
              return $this;
          }
          $this->queue[] = $middleware;
  
          return $this;
      }
code: public function add($middleware)
      {
          if (is_array($middleware)) {
              $this->queue = array_merge($this->queue, $middleware);
  
              return $this;
          }
          $this->queue[] = $middleware;
  
          return $this;
      }
code_tokens: public function add ( $ middleware ) { if ( is_array ( $ middleware ) ) { $ this -> queue = array_merge ( $ this -> queue , $ middleware ) ; return $ this ; } $ this -> queue [ ] = $ middleware ; return $ this ; }
docstring: Append a middleware callable to the end of the queue.
  
  @param callable|string|array $middleware The middleware(s) to append.
  @return $this
docstring_tokens: Append a middleware callable to the end of the queue .