{"ast_node_type":"other","tokens":[{"end":84,"kind":"keyword","start":0,"text":"self.demand_eqtype_pat(span,"}]}
                self.demand_eqtype_pat(span, expected, box_ty, &pat_info.top_info)?;
                let box_ty = Ty::new_box(tcx, inner_ty);
                Ok((box_ty, inner_ty))