original_string: protected function merge()
      {
          if (null === $this->merge) {
              $this->merge = new MergeBuilder($this);
          }
  
          return $this->merge;
      }
code: protected function merge()
      {
          if (null === $this->merge) {
              $this->merge = new MergeBuilder($this);
          }
  
          return $this->merge;
      }
code_tokens: protected function merge ( ) { if ( null === $ this -> merge ) { $ this -> merge = new MergeBuilder ( $ this ) ; } return $ this -> merge ; }
docstring: Gets the builder for merging rules.
  
  @return MergeBuilder
docstring_tokens: Gets the builder for merging rules .