public function filter(\Closure $c)
 {
     $filtered = $this->expression->filter($c);
     if ($this->codeChunks !== null) {
         foreach ($this->codeChunks->getCodeChunks() as $codeChunk) {
             $filtered = array_merge($filtered, $codeChunk->filter($c));
         }
     }
     return $filtered;
 }
 public function filter(\Closure $c)
 {
     return array_merge($this->leftValue->filter($c), $this->rightValue->filter($c));
 }