add base object arol object abas classifi role role classifi role arol classifi base classifi abas role base illeg argument except add base role base todo check probabl belong critic instead rule violat later name clear name uniqu role base illeg argument except add base base role role doe role base add base model impl facad base role size role avail content clear role avail content add base own element role avail featur clear role avail featur add base featur model element elem base own element role avail content contain elem role avail content add elem featur featur base featur role avail featur contain featur role avail featur add featur 