{"ast_node_type":"function","tokens":[{"end":55,"kind":"keyword","start":0,"text":"fn"}]}
        fn visit_const(&mut self, c: ty::Const<'tcx>) {
    impl<'tcx> TypeVisitor<TyCtxt<'tcx>> for ConstCollector<'tcx> {
            if let ty::ConstKind::Unevaluated(uv) = c.kind() {