{"ast_node_type":"other","tokens":[{"end":55,"kind":"keyword","start":0,"text":")"}]}
    ) -> Result<TyCtxtFeed<'tcx, CrateNum>, CrateNum> {
        stable_crate_id: StableCrateId,
        if let Some(&existing) = self.untracked().stable_crate_ids.read().get(&stable_crate_id) {