original_string: public function description() {
          list($missingparent, $loops) = $this->find_problems();
  
          $description = '<p>The course categories should be arranged into tree ' .
                  ' structures by the course_categories.parent field. Sometimes ' .
                  ' this tree structure gets messed up.</p>';
  
          $description .= tool_health_category_list_missing_parents($missingparent);
          $description .= tool_health_category_list_loops($loops);
  
          return $description;
      }
code: public function description() {
          list($missingparent, $loops) = $this->find_problems();
  
          $description = '<p>The course categories should be arranged into tree ' .
                  ' structures by the course_categories.parent field. Sometimes ' .
                  ' this tree structure gets messed up.</p>';
  
          $description .= tool_health_category_list_missing_parents($missingparent);
          $description .= tool_health_category_list_loops($loops);
  
          return $description;
      }
code_tokens: public function description ( ) { list ( $ missingparent , $ loops ) = $ this -> find_problems ( ) ; $ description = '<p>The course categories should be arranged into tree ' . ' structures by the course_categories.parent field. Sometimes ' . ' this tree structure gets messed up.</p>' ; $ description .= tool_health_category_list_missing_parents ( $ missingparent ) ; $ description .= tool_health_category_list_loops ( $ loops ) ; return $ description ; }
docstring: Generate problem description.
  
  @return string HTML containing details of the problem.
docstring_tokens: Generate problem description .