{"ast_node_type":"variable","tokens":[{"end":37,"kind":"keyword","start":0,"text":"let"}]}
        let def_id = match a.kind() {
    ) -> RelateResult<'tcx, ty::Region<'tcx>> {
            ty::ReEarlyParam(ebr) => self.generics.region_param(ebr, self.tcx).def_id,