code: public function toArray()
      {
          return [
              'id'          => $this->id,
              'curie'       => $this->getCurie(),
              'curie_major' => $this->getCurieMajor(),
              'qname'       => $this->getQName(),
              'class_name'  => $this->className,
              'mixins'      => array_map(
                  function (Mixin $mixin) {
                      return $mixin->getId();
                  },
                  array_values($this->mixins)
              ),
              'fields'      => $this->fields,
          ];
      }
docs: {@inheritdoc}