original_string: public function equalFields($left, $right)
      {
          $wrapIdentifier = function ($field) {
              if ($field instanceof ExpressionInterface) {
                  return $field;
              }
  
              return new IdentifierExpression($field);
          };
  
          return $this->eq($wrapIdentifier($left), $wrapIdentifier($right));
      }
code: public function equalFields($left, $right)
      {
          $wrapIdentifier = function ($field) {
              if ($field instanceof ExpressionInterface) {
                  return $field;
              }
  
              return new IdentifierExpression($field);
          };
  
          return $this->eq($wrapIdentifier($left), $wrapIdentifier($right));
      }
code_tokens: public function equalFields ( $ left , $ right ) { $ wrapIdentifier = function ( $ field ) { if ( $ field instanceof ExpressionInterface ) { return $ field ; } return new IdentifierExpression ( $ field ) ; } ; return $ this -> eq ( $ wrapIdentifier ( $ left ) , $ wrapIdentifier ( $ right ) ) ; }
docstring: Builds equal condition or assignment with identifier wrapping.
  
  @param string $left Left join condition field name.
  @param string $right Right join condition field name.
  @return $this
docstring_tokens: Builds equal condition or assignment with identifier wrapping .