original_string: private static function mandatory($feature) {
          if ($feature->getParent() && $feature->getMandatory())
              return Logic::equiv(Logic::is($feature), Logic::is($feature->getParent()));
      }
code: private static function mandatory($feature) {
          if ($feature->getParent() && $feature->getMandatory())
              return Logic::equiv(Logic::is($feature), Logic::is($feature->getParent()));
      }
code_tokens: private static function mandatory ( $ feature ) { if ( $ feature -> getParent ( ) && $ feature -> getMandatory ( ) ) return Logic :: equiv ( Logic :: is ( $ feature ) , Logic :: is ( $ feature -> getParent ( ) ) ) ; }
docstring: Semantics for a mandatory feature.
  A mandatory feature is selected iff its parent is selected.
  @param Feature $feature
  @return callable
docstring_tokens: Semantics for a mandatory feature . A mandatory feature is selected iff its parent is selected .