{"ast_node_type":"variable","tokens":[{"end":85,"kind":"keyword","start":0,"text":"let"}]}
                let ty = self.db.impl_self_ty(impl_id).substitute(Interner, &substs);
                let substs = generics.placeholder_subst(self.db);
                return if let Some((AdtId::StructId(struct_id), substs)) = ty.as_adt() {