{"ast_node_type":"variable","tokens":[{"end":79,"kind":"keyword","start":0,"text":"if"}]}
                if let ty::RegionKind::ReBound(ty::INNERMOST, bv) = re.kind() {
            ty::GenericArgKind::Lifetime(re) => {
                    mapping.insert(bv.var, tcx.mk_param_from_def(param))