{"ast_node_type":"variable","tokens":[{"end":55,"kind":"keyword","start":0,"text":"let"}]}
            let variant_index = VariantIdx::new(index);
        for (index, state_tys) in args.state_tys(coroutine_def_id, self.tcx).enumerate() {
            let dest = self.tcx.mk_place_downcast_unnamed(dest, variant_index);