docs: public boolean isFullyDefinedType( Name primaryTypeName,
                                         Set<Name> mixinTypeNames ) {
          if (!fullyDefinedNodeTypes.contains(primaryTypeName)) return false;
          if (!mixinTypeNames.isEmpty()) {
              for (Name nodeTypeName : mixinTypeNames) {
                  if (!fullyDefinedNodeTypes.contains(nodeTypeName)) return false;
              }
          }
          return true;
      }