{"ast_node_type":"variable","tokens":[{"end":99,"kind":"keyword","start":0,"text":"let"}]}
                        let hir::ItemKind::Impl(hir::Impl { of_trait: Some(trait_ref), .. }) = self
                    Res::SelfTyAlias { alias_to: impl_def_id, is_trait_impl: true, .. } => {
                            .tcx