original_string: private function getPreviousUrl(PaginatorInterface $paginator) : ?string
      {
          $page = $paginator->getCurrentPage();
  
          if (--$page >= 1) {
              return $this->generateUrl(
                  $this->getRoute(),
                  $this->getMergedParams(['page' => $page])
              );
          }
  
          return null;
      }
code: private function getPreviousUrl(PaginatorInterface $paginator) : ?string
      {
          $page = $paginator->getCurrentPage();
  
          if (--$page >= 1) {
              return $this->generateUrl(
                  $this->getRoute(),
                  $this->getMergedParams(['page' => $page])
              );
          }
  
          return null;
      }
code_tokens: private function getPreviousUrl ( PaginatorInterface $ paginator ) : ? string { $ page = $ paginator -> getCurrentPage ( ) ; if ( -- $ page >= 1 ) { return $ this -> generateUrl ( $ this -> getRoute ( ) , $ this -> getMergedParams ( [ 'page' => $ page ] ) ) ; } return null ; }
docstring: Get previous URL
  
  @param PaginatorInterface $paginator
  
  @return string|null
docstring_tokens: Get previous URL