{"ast_node_type":"variable","tokens":[{"end":97,"kind":"keyword","start":0,"text":"let"}]}
        let (def_id, hir_id, idx, flavor) = match *error.obligation.cause.code().peel_derives() {
    ) -> bool {
            ObligationCauseCode::WhereClauseInExpr(def_id, _, hir_id, idx) => {