{"ast_node_type":"other","tokens":[{"end":56,"kind":"keyword","start":0,"text":"RigidTy::Adt(def,"}]}
            RigidTy::Adt(def, args) if def.is_box() => {
        match self.rigid()? {
                Some(TypeAndMut { ty: *args.0.first()?.ty()?, mutability: Mutability::Not })