{"ast_node_type":"variable","tokens":[{"end":70,"kind":"keyword","start":0,"text":"let"}]}
                let error_term = match goal.predicate.alias.kind(cx) {
            let error_response = |ecx: &mut EvalCtxt<'_, D>, guar| {
                    ty::AliasTermKind::ProjectionTy => Ty::new_error(cx, guar).into(),