-dsGRHS hs_ctx pats rhs_ty (L loc (GRHS guards rhs))
- = matchGuards (map unLoc guards) hs_ctx rhs rhs_ty
+dsGRHS :: HsMatchContext Name -> [Pat Id] -> Type -> LGRHS Id -> DsM MatchResult
+dsGRHS hs_ctx _ rhs_ty (L _ (GRHS guards rhs))
+ = matchGuards (map unLoc guards) (PatGuard hs_ctx) rhs rhs_ty