{"ast_node_type":"other","tokens":[{"end":35,"kind":"keyword","start":0,"text":"type"}]}
            type Extra = $extra_ty;
        impl<$lt, $vis_ty: Visitor<$lt>> Visitable<$lt, $vis_ty> for $self_ty {
            fn visit(&$lt $self, $vis: &mut $vis_ty, $extra: Self::Extra) -> V::Result {