printOptUnion :: LogicGraph -> Annoted SPEC -> [Doc]
printOptUnion lg x = case skipVoidGroup $ item x of
        Union e@(_ : _) _ -> printUnion lg $ moveAnnos x e
        Extension e@(_ : _) _ -> printExtension lg $ moveAnnos x e
        _ -> [prettyLG lg x]
printOptUnion :: LogicGraph -> Annoted SPEC -> [Doc]
printOptUnion lg x = case skipVoidGroup $ item x of
        Union e@(_ : _) _ -> printUnion lg $ moveAnnos x e
        Extension e@(_ : _) _ -> printExtension lg $ moveAnnos x e
        _ -> [prettyLG lg x]
printOptUnion lg x = case skipVoidGroup $ item x of
        Union e@(_ : _) _ -> printUnion lg $ moveAnnos x e
        Extension e@(_ : _) _ -> printExtension lg $ moveAnnos x e
        _ -> [prettyLG lg x]