original_string: public function get_heading_before_slot($slot) {
          if ($this->slots[$slot]->firstinsection) {
              return $this->slots[$slot]->section->heading;
          } else {
              return null;
          }
      }
code: public function get_heading_before_slot($slot) {
          if ($this->slots[$slot]->firstinsection) {
              return $this->slots[$slot]->section->heading;
          } else {
              return null;
          }
      }
code_tokens: public function get_heading_before_slot ( $ slot ) { if ( $ this -> slots [ $ slot ] -> firstinsection ) { return $ this -> slots [ $ slot ] -> section -> heading ; } else { return null ; } }
docstring: If the section heading, if any, that should come just before this slot.
  @param int $slot identifies a particular question in this attempt.
  @return string the required heading, or null if there is not one here.
docstring_tokens: If the section heading if any that should come just before this slot .