original_string: public function exists() {
          list($missingparent, $loops) = $this->find_problems();
          return !empty($missingparent) || !empty($loops);
      }
code: public function exists() {
          list($missingparent, $loops) = $this->find_problems();
          return !empty($missingparent) || !empty($loops);
      }
code_tokens: public function exists ( ) { list ( $ missingparent , $ loops ) = $ this -> find_problems ( ) ; return ! empty ( $ missingparent ) || ! empty ( $ loops ) ; }
docstring: Check if the problem exists.
  
  @return boolean True if either missing parents or loops found
docstring_tokens: Check if the problem exists .