%* *
%************************************************************************
-\begin{code}
-mkDataConAlt :: DataCon -> [OutType] -> InExpr -> SimplM InAlt
--- Make a data-constructor alternative to replace the DEFAULT case
--- NB: there's something a bit bogus here, because we put OutTypes into an InAlt
-mkDataConAlt con inst_tys rhs
- = ASSERT(not (isNewTyCon (dataConTyCon con)))
- do { tv_uniqs <- getUniquesSmpl
- ; arg_uniqs <- getUniquesSmpl
- ; let tv_bndrs = zipWith mk_tv_bndr (dataConExTyVars con) tv_uniqs
- arg_tys = dataConInstArgTys con (inst_tys ++ mkTyVarTys tv_bndrs)
- arg_bndrs = zipWith mk_arg arg_tys arg_uniqs
- ; return (DataAlt con, tv_bndrs ++ arg_bndrs, rhs) }
- where
- mk_arg arg_ty uniq -- Equality predicates get a TyVar
- -- while dictionaries and others get an Id
- | isEqPredTy arg_ty = mk_tv arg_ty uniq
- | otherwise = mk_id arg_ty uniq
-
- mk_tv_bndr tv uniq = mk_tv (tyVarKind tv) uniq
- mk_tv kind uniq = mkTyVar (mkSysTvName uniq FSLIT("t")) kind
- mk_id ty uniq = mkSysLocal FSLIT("a") uniq ty
-\end{code}
mkCase puts a case expression back together, trying various transformations first.