{"ast_node_type":"other","tokens":[{"end":56,"kind":"keyword","start":0,"text":"RegionSubRegion(ty::Region<'tcx>,"}]}
    RegionSubRegion(ty::Region<'tcx>, ty::Region<'tcx>),
pub enum OutlivesBound<'tcx> {
    RegionSubParam(ty::Region<'tcx>, ty::ParamTy),