{"ast_node_type":"variable","tokens":[{"end":49,"kind":"keyword","start":0,"text":"let"}]}
        let ty = self.lowerer().lower_ty(hir_ty);
    pub(crate) fn lower_ty(&self, hir_ty: &hir::Ty<'tcx>) -> LoweredTy<'tcx> {
        self.register_wf_obligation(ty.into(), hir_ty.span, ObligationCauseCode::WellFormed(None));