module DsExpr ( dsExpr ) where
-import Ubiq
-import DsLoop -- partly to get dsBinds, partly to chk dsExpr
-
-import HsSyn ( HsExpr(..), HsLit(..), ArithSeqInfo(..),
- Match, Qual, HsBinds, Stmt, PolyType )
-import TcHsSyn ( TypecheckedHsExpr(..), TypecheckedHsBinds(..) )
+IMP_Ubiq()
+IMPORT_DELOOPER(DsLoop) -- partly to get dsBinds, partly to chk dsExpr
+
+import HsSyn ( failureFreePat,
+ HsExpr(..), OutPat(..), HsLit(..), ArithSeqInfo(..),
+ Stmt(..), Match(..), Qualifier, HsBinds, PolyType,
+ GRHSsAndBinds
+ )
+import TcHsSyn ( TypecheckedHsExpr(..), TypecheckedHsBinds(..),
+ TypecheckedRecordBinds(..), TypecheckedPat(..),
+ TypecheckedStmt(..)
+ )
import CoreSyn
import DsMonad
import DsCCall ( dsCCall )
+import DsHsSyn ( outPatType )
import DsListComp ( dsListComp )
-import DsUtils ( mkAppDs, mkConDs, mkPrimDs, dsExprToAtom )
+import DsUtils ( mkAppDs, mkConDs, mkPrimDs, dsExprToAtom,
+ mkErrorAppDs, showForErr, EquationInfo,
+ MatchResult, DsCoreArg(..)
+ )
import Match ( matchWrapper )
import CoreUnfold ( UnfoldingDetails(..), UnfoldingGuidance(..),
import CoreUtils ( coreExprType, substCoreExpr, argToExpr,
mkCoreIfThenElse, unTagBinders )
import CostCentre ( mkUserCC )
+import FieldLabel ( fieldLabelType, FieldLabel )
import Id ( mkTupleCon, idType, nullIdEnv, addOneToIdEnv,
- getIdUnfolding )
+ getIdUnfolding, dataConArgTys, dataConFieldLabels,
+ recordSelectorFieldLabel
+ )
import Literal ( mkMachInt, Literal(..) )
import MagicUFs ( MagicUnfoldingFun )
+import Name ( Name{--O only-} )
import PprStyle ( PprStyle(..) )
-import PprType ( GenType, GenTyVar )
-import PrelInfo ( mkTupleTy, unitTy, nilDataCon, consDataCon,
- charDataCon, charTy )
-import Pretty ( ppShow )
-import Type ( splitSigmaTy )
-import TyVar ( nullTyVarEnv, addOneToTyVarEnv, GenTyVar )
-import Unique ( Unique )
-import Usage ( UVar(..) )
-import Util ( panic )
-
-primRepFromType = panic "DsExpr.primRepFromType"
-maybeBoxedPrimType = panic "DsExpr.maybeBoxedPrimType"
-splitTyArgs = panic "DsExpr.splitTyArgs"
+import PprType ( GenType )
+import PrelVals ( rEC_CON_ERROR_ID, rEC_UPD_ERROR_ID, voidId )
+import Pretty ( ppShow, ppBesides, ppPStr, ppStr )
+import TyCon ( isDataTyCon, isNewTyCon )
+import Type ( splitSigmaTy, splitFunTy, typePrimRep,
+ getAppDataTyConExpandingDicts, getAppTyCon, applyTy,
+ maybeBoxedPrimType
+ )
+import TysPrim ( voidTy )
+import TysWiredIn ( mkTupleTy, nilDataCon, consDataCon,
+ charDataCon, charTy
+ )
+import TyVar ( nullTyVarEnv, addOneToTyVarEnv, GenTyVar{-instance Eq-} )
+import Usage ( SYN_IE(UVar) )
+import Util ( zipEqual, pprError, panic, assertPanic )
mk_nil_con ty = mkCon nilDataCon [] [ty] [] -- micro utility...
\end{code}
the_char = mkCon charDataCon [] [] [LitArg (MachChar (_HEAD_ s))]
the_nil = mk_nil_con charTy
in
- mkConDs consDataCon [charTy] [the_char, the_nil]
+ mkConDs consDataCon [TyArg charTy, VarArg the_char, VarArg the_nil]
-- "_" => build (\ c n -> c 'c' n) -- LATER
-- "str" ==> build (\ c n -> foldr charTy T c n "str")
{- LATER:
-dsExpr (HsLitOut (HsString str) _) =
- newTyVarsDs [alphaTyVar] `thenDs` \ [new_tyvar] ->
+dsExpr (HsLitOut (HsString str) _)
+ = newTyVarsDs [alphaTyVar] `thenDs` \ [new_tyvar] ->
let
new_ty = mkTyVarTy new_tyvar
in
where
(data_con, kind)
= case (maybeBoxedPrimType ty) of
- Nothing
- -> error ("ERROR: ``literal-literal'' not a single-constructor type: "++ _UNPK_ s ++"; type: "++(ppShow 80 (ppr PprDebug ty)))
Just (boxing_data_con, prim_ty)
- -> (boxing_data_con, primRepFromType prim_ty)
+ -> (boxing_data_con, typePrimRep prim_ty)
+ Nothing
+ -> pprError "ERROR: ``literal-literal'' not a single-constructor type: "
+ (ppBesides [ppPStr s, ppStr "; type: ", ppr PprDebug ty])
-dsExpr (HsLitOut (HsInt i) _)
- = returnDs (Lit (NoRepInteger i))
+dsExpr (HsLitOut (HsInt i) ty)
+ = returnDs (Lit (NoRepInteger i ty))
-dsExpr (HsLitOut (HsFrac r) _)
- = returnDs (Lit (NoRepRational r))
+dsExpr (HsLitOut (HsFrac r) ty)
+ = returnDs (Lit (NoRepRational r ty))
-- others where we know what to do:
-- end of literals magic. --
dsExpr expr@(HsLam a_Match)
- = let
- error_msg = "%L" --> "pattern-matching failed in lambda"
- in
- matchWrapper LambdaMatch [a_Match] error_msg `thenDs` \ (binders, matching_code) ->
+ = matchWrapper LambdaMatch [a_Match] "lambda" `thenDs` \ (binders, matching_code) ->
returnDs ( mkValLam binders matching_code )
dsExpr expr@(HsApp e1 e2) = dsApp expr []
dsExpr (SectionL expr op)
= dsExpr op `thenDs` \ core_op ->
dsExpr expr `thenDs` \ core_expr ->
- dsExprToAtom core_expr $ \ y_atom ->
+ dsExprToAtom (VarArg core_expr) $ \ y_atom ->
-- for the type of x, we need the type of op's 2nd argument
let
x_ty = case (splitSigmaTy (coreExprType core_op)) of { (_, _, tau_ty) ->
- case (splitTyArgs tau_ty) of {
+ case (splitFunTy tau_ty) of {
((_:arg2_ty:_), _) -> arg2_ty;
- _ -> panic "dsExpr:SectionL:arg 2 ty"
- }}
+ _ -> panic "dsExpr:SectionL:arg 2 ty" }}
in
newSysLocalDs x_ty `thenDs` \ x_id ->
returnDs (mkValLam [x_id] (core_op `App` y_atom `App` VarArg x_id))
dsExpr (SectionR op expr)
= dsExpr op `thenDs` \ core_op ->
dsExpr expr `thenDs` \ core_expr ->
- dsExprToAtom core_expr $ \ y_atom ->
+ dsExprToAtom (VarArg core_expr) $ \ y_atom ->
-- for the type of x, we need the type of op's 1st argument
let
x_ty = case (splitSigmaTy (coreExprType core_op)) of { (_, _, tau_ty) ->
- case (splitTyArgs tau_ty) of {
+ case (splitFunTy tau_ty) of {
((arg1_ty:_), _) -> arg1_ty;
- _ -> panic "dsExpr:SectionR:arg 1 ty"
- }}
+ _ -> panic "dsExpr:SectionR:arg 1 ty" }}
in
newSysLocalDs x_ty `thenDs` \ x_id ->
returnDs (mkValLam [x_id] (core_op `App` VarArg x_id `App` y_atom))
dsExpr expr@(HsCase discrim matches src_loc)
= putSrcLocDs src_loc $
- dsExpr discrim `thenDs` \ core_discrim ->
- let
- error_msg = "%C" --> "pattern-matching failed in case"
- in
- matchWrapper CaseMatch matches error_msg `thenDs` \ ([discrim_var], matching_code) ->
+ dsExpr discrim `thenDs` \ core_discrim ->
+ matchWrapper CaseMatch matches "case" `thenDs` \ ([discrim_var], matching_code) ->
returnDs ( mkCoLetAny (NonRec discrim_var core_discrim) matching_code )
dsExpr (ListComp expr quals)
dsListComp core_expr quals
dsExpr (HsLet binds expr)
- = dsBinds binds `thenDs` \ core_binds ->
+ = dsBinds False binds `thenDs` \ core_binds ->
dsExpr expr `thenDs` \ core_expr ->
returnDs ( mkCoLetsAny core_binds core_expr )
-dsExpr (HsDoOut stmts m_id mz_id src_loc)
+dsExpr (HsDoOut stmts then_id zero_id src_loc)
= putSrcLocDs src_loc $
- panic "dsExpr:HsDoOut"
+ dsDo then_id zero_id stmts
+
+dsExpr (HsIf guard_expr then_expr else_expr src_loc)
+ = putSrcLocDs src_loc $
+ dsExpr guard_expr `thenDs` \ core_guard ->
+ dsExpr then_expr `thenDs` \ core_then ->
+ dsExpr else_expr `thenDs` \ core_else ->
+ returnDs (mkCoreIfThenElse core_guard core_then core_else)
+\end{code}
+
+
+Type lambda and application
+~~~~~~~~~~~~~~~~~~~~~~~~~~~
+\begin{code}
+dsExpr (TyLam tyvars expr)
+ = dsExpr expr `thenDs` \ core_expr ->
+ returnDs (mkTyLam tyvars core_expr)
+
+dsExpr expr@(TyApp e tys) = dsApp expr []
+\end{code}
+
+Various data construction things
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+\begin{code}
dsExpr (ExplicitListOut ty xs)
= case xs of
[] -> returnDs (mk_nil_con ty)
(y:ys) ->
dsExpr y `thenDs` \ core_hd ->
dsExpr (ExplicitListOut ty ys) `thenDs` \ core_tl ->
- mkConDs consDataCon [ty] [core_hd, core_tl]
+ mkConDs consDataCon [TyArg ty, VarArg core_hd, VarArg core_tl]
dsExpr (ExplicitTuple expr_list)
= mapDs dsExpr expr_list `thenDs` \ core_exprs ->
mkConDs (mkTupleCon (length expr_list))
- (map coreExprType core_exprs)
- core_exprs
+ (map (TyArg . coreExprType) core_exprs ++ map VarArg core_exprs)
-dsExpr (RecordCon con rbinds) = panic "dsExpr:RecordCon"
-dsExpr (RecordUpd aexp rbinds) = panic "dsExpr:RecordUpd"
+-- Two cases, one for ordinary constructors and one for newtype constructors
+dsExpr (HsCon con tys args)
+ | isDataTyCon tycon -- The usual datatype case
+ = mapDs dsExpr args `thenDs` \ args_exprs ->
+ mkConDs con (map TyArg tys ++ map VarArg args_exprs)
-dsExpr (HsIf guard_expr then_expr else_expr src_loc)
- = putSrcLocDs src_loc $
- dsExpr guard_expr `thenDs` \ core_guard ->
- dsExpr then_expr `thenDs` \ core_then ->
- dsExpr else_expr `thenDs` \ core_else ->
- returnDs (mkCoreIfThenElse core_guard core_then core_else)
+ | otherwise -- The newtype case
+ = ASSERT( isNewTyCon tycon )
+ ASSERT( null rest_args )
+ dsExpr first_arg `thenDs` \ arg_expr ->
+ returnDs (Coerce (CoerceIn con) result_ty arg_expr)
+
+ where
+ (first_arg:rest_args) = args
+ (args_tys, result_ty) = splitFunTy (foldl applyTy (idType con) tys)
+ (tycon,_) = getAppTyCon result_ty
dsExpr (ArithSeqOut expr (From from))
= dsExpr expr `thenDs` \ expr2 ->
dsExpr from `thenDs` \ from2 ->
- mkAppDs expr2 [] [from2]
+ mkAppDs expr2 [VarArg from2]
dsExpr (ArithSeqOut expr (FromTo from two))
= dsExpr expr `thenDs` \ expr2 ->
dsExpr from `thenDs` \ from2 ->
dsExpr two `thenDs` \ two2 ->
- mkAppDs expr2 [] [from2, two2]
+ mkAppDs expr2 [VarArg from2, VarArg two2]
dsExpr (ArithSeqOut expr (FromThen from thn))
= dsExpr expr `thenDs` \ expr2 ->
dsExpr from `thenDs` \ from2 ->
dsExpr thn `thenDs` \ thn2 ->
- mkAppDs expr2 [] [from2, thn2]
+ mkAppDs expr2 [VarArg from2, VarArg thn2]
dsExpr (ArithSeqOut expr (FromThenTo from thn two))
= dsExpr expr `thenDs` \ expr2 ->
dsExpr from `thenDs` \ from2 ->
dsExpr thn `thenDs` \ thn2 ->
dsExpr two `thenDs` \ two2 ->
- mkAppDs expr2 [] [from2, thn2, two2]
+ mkAppDs expr2 [VarArg from2, VarArg thn2, VarArg two2]
\end{code}
+Record construction and update
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+For record construction we do this (assuming T has three arguments)
+
+ T { op2 = e }
+==>
+ let err = /\a -> recConErr a
+ T (recConErr t1 "M.lhs/230/op1")
+ e
+ (recConErr t1 "M.lhs/230/op3")
+
+recConErr then converts its arugment string into a proper message
+before printing it as
+
+ M.lhs, line 230: missing field op1 was evaluated
+
+
\begin{code}
-dsExpr (TyLam tyvars expr)
- = dsExpr expr `thenDs` \ core_expr ->
- returnDs (mkTyLam tyvars core_expr)
+dsExpr (RecordCon con_expr rbinds)
+ = dsExpr con_expr `thenDs` \ con_expr' ->
+ let
+ con_id = get_con con_expr'
+ (arg_tys, _) = splitFunTy (coreExprType con_expr')
+
+ mk_arg (arg_ty, lbl)
+ = case [rhs | (sel_id,rhs,_) <- rbinds,
+ lbl == recordSelectorFieldLabel sel_id] of
+ (rhs:rhss) -> ASSERT( null rhss )
+ dsExpr rhs
+ [] -> mkErrorAppDs rEC_CON_ERROR_ID arg_ty (showForErr lbl)
+ in
+ mapDs mk_arg (zipEqual "dsExpr:RecordCon" arg_tys (dataConFieldLabels con_id)) `thenDs` \ con_args ->
+ mkAppDs con_expr' (map VarArg con_args)
+ where
+ -- "con_expr'" is simply an application of the constructor Id
+ -- to types and (perhaps) dictionaries. This gets the constructor...
+ get_con (Var con) = con
+ get_con (App fun _) = get_con fun
+\end{code}
-dsExpr expr@(TyApp e tys) = dsApp expr []
+Record update is a little harder. Suppose we have the decl:
+
+ data T = T1 {op1, op2, op3 :: Int}
+ | T2 {op4, op2 :: Int}
+ | T3
+
+Then we translate as follows:
+
+ r { op2 = e }
+===>
+ let op2 = e in
+ case r of
+ T1 op1 _ op3 -> T1 op1 op2 op3
+ T2 op4 _ -> T2 op4 op2
+ other -> recUpdError "M.lhs/230"
+
+It's important that we use the constructor Ids for T1, T2 etc on the
+RHSs, and do not generate a Core Con directly, because the constructor
+might do some argument-evaluation first; and may have to throw away some
+dictionaries.
+
+\begin{code}
+dsExpr (RecordUpdOut record_expr dicts rbinds)
+ = dsExpr record_expr `thenDs` \ record_expr' ->
+
+ -- Desugar the rbinds, and generate let-bindings if
+ -- necessary so that we don't lose sharing
+ dsRbinds rbinds $ \ rbinds' ->
+ let
+ record_ty = coreExprType record_expr'
+ (tycon, inst_tys, cons) = trace "DsExpr.getAppDataTyConExpandingDicts" $
+ getAppDataTyConExpandingDicts record_ty
+ cons_to_upd = filter has_all_fields cons
+
+ -- initial_args are passed to every constructor
+ initial_args = map TyArg inst_tys ++ map VarArg dicts
+
+ mk_val_arg (field, arg_id)
+ = case [arg | (f, arg) <- rbinds',
+ field == recordSelectorFieldLabel f] of
+ (arg:args) -> ASSERT(null args)
+ arg
+ [] -> VarArg arg_id
+
+ mk_alt con
+ = newSysLocalsDs (dataConArgTys con inst_tys) `thenDs` \ arg_ids ->
+ let
+ val_args = map mk_val_arg (zipEqual "dsExpr:RecordUpd" (dataConFieldLabels con) arg_ids)
+ in
+ returnDs (con, arg_ids, mkGenApp (mkGenApp (Var con) initial_args) val_args)
+
+ mk_default
+ | length cons_to_upd == length cons
+ = returnDs NoDefault
+ | otherwise
+ = newSysLocalDs record_ty `thenDs` \ deflt_id ->
+ mkErrorAppDs rEC_UPD_ERROR_ID record_ty "" `thenDs` \ err ->
+ returnDs (BindDefault deflt_id err)
+ in
+ mapDs mk_alt cons_to_upd `thenDs` \ alts ->
+ mk_default `thenDs` \ deflt ->
+
+ returnDs (Case record_expr' (AlgAlts alts deflt))
+
+ where
+ has_all_fields :: Id -> Bool
+ has_all_fields con_id
+ = all ok rbinds
+ where
+ con_fields = dataConFieldLabels con_id
+ ok (sel_id, _, _) = recordSelectorFieldLabel sel_id `elem` con_fields
\end{code}
+Dictionary lambda and application
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
@DictLam@ and @DictApp@ turn into the regular old things.
(OLD:) @DictFunApp@ also becomes a curried application, albeit slightly more
complicated; reminiscent of fully-applied constructors.
`thenDs` \ core_d_and_ms ->
(case num_of_d_and_ms of
- 0 -> returnDs cocon_unit -- unit
+ 0 -> returnDs (Var voidId)
1 -> returnDs (head core_d_and_ms) -- just a single Id
_ -> -- tuple 'em up
mkConDs (mkTupleCon num_of_d_and_ms)
- (map coreExprType core_d_and_ms)
- core_d_and_ms
+ (map (TyArg . coreExprType) core_d_and_ms ++ map VarArg core_d_and_ms)
)
where
dicts_and_methods = dicts ++ methods
dsExpr (ClassDictLam dicts methods expr)
= dsExpr expr `thenDs` \ core_expr ->
case num_of_d_and_ms of
- 0 -> newSysLocalDs unitTy `thenDs` \ new_x ->
+ 0 -> newSysLocalDs voidTy `thenDs` \ new_x ->
returnDs (mkValLam [new_x] core_expr)
1 -> -- no untupling
dsExpr (ArithSeqIn _) = panic "dsExpr:ArithSeqIn"
#endif
-cocon_unit = mkCon (mkTupleCon 0) [] [] [] -- out here to avoid CAF (sigh)
out_of_range_msg -- ditto
= " out of range: [" ++ show minInt ++ ", " ++ show maxInt ++ "]\n"
\end{code}
possible).
\begin{code}
-type DsCoreArg = GenCoreArg CoreExpr{-NB!-} TyVar UVar
-
dsApp :: TypecheckedHsExpr -- expr to desugar
-> [DsCoreArg] -- accumulated ty/val args: NB:
-> DsM CoreExpr -- final result
dsApp (HsVar v) args
= lookupEnvDs v `thenDs` \ maybe_expr ->
case maybe_expr of
- Just expr -> apply_to_args expr args
+ Just expr -> mkAppDs expr args
Nothing -> -- we're only saturating constructors and PrimOps
case getIdUnfolding v of
- GenForm _ _ the_unfolding EssentialUnfolding
+ GenForm _ the_unfolding EssentialUnfolding
-> do_unfold nullTyVarEnv nullIdEnv (unTagBinders the_unfolding) args
- _ -> apply_to_args (Var v) args
+ _ -> mkAppDs (Var v) args
dsApp anything_else args
= dsExpr anything_else `thenDs` \ core_expr ->
- apply_to_args core_expr args
-
--- a DsM version of mkGenApp:
-apply_to_args :: CoreExpr -> [DsCoreArg] -> DsM CoreExpr
-
-apply_to_args fun args
- = let
- (ty_args, val_args) = foldr sep ([],[]) args
- in
- mkAppDs fun ty_args val_args
- where
- sep a@(LitArg l) (tys,vals) = (tys, (Lit l):vals)
- sep a@(VarArg e) (tys,vals) = (tys, e:vals)
- sep a@(TyArg ty) (tys,vals) = (ty:tys, vals)
- sep a@(UsageArg _) _ = panic "DsExpr:apply_to_args:UsageArg"
+ mkAppDs core_expr args
\end{code}
\begin{code}
+dsRbinds :: TypecheckedRecordBinds -- The field bindings supplied
+ -> ([(Id, CoreArg)] -> DsM CoreExpr) -- A continuation taking the field
+ -- bindings with atomic rhss
+ -> DsM CoreExpr -- The result of the continuation,
+ -- wrapped in suitable Lets
+
+dsRbinds [] continue_with
+ = continue_with []
+
+dsRbinds ((sel_id, rhs, pun_flag) : rbinds) continue_with
+ = dsExpr rhs `thenDs` \ rhs' ->
+ dsExprToAtom (VarArg rhs') $ \ rhs_atom ->
+ dsRbinds rbinds $ \ rbinds' ->
+ continue_with ((sel_id, rhs_atom) : rbinds')
+\end{code}
+
+\begin{code}
do_unfold ty_env val_env (Lam (TyBinder tyvar) body) (TyArg ty : args)
= do_unfold (addOneToTyVarEnv ty_env tyvar ty) val_env body args
-do_unfold ty_env val_env (Lam (ValBinder binder) body) (VarArg expr : args)
- = dsExprToAtom expr $ \ arg_atom ->
+do_unfold ty_env val_env (Lam (ValBinder binder) body) (arg@(VarArg expr) : args)
+ = dsExprToAtom arg $ \ arg_atom ->
do_unfold ty_env
(addOneToIdEnv val_env binder (argToExpr arg_atom))
body args
uniqSMtoDsM (substCoreExpr val_env ty_env body) `thenDs` \ body' ->
-- Apply result to remaining arguments
- apply_to_args body' args
+ mkAppDs body' args
+\end{code}
+
+Basically does the translation given in the Haskell~1.3 report:
+\begin{code}
+dsDo :: Id -- id for: (>>=) m
+ -> Id -- id for: zero m
+ -> [TypecheckedStmt]
+ -> DsM CoreExpr
+
+dsDo then_id zero_id (stmt:stmts)
+ = case stmt of
+ ExprStmt expr locn -> ASSERT( null stmts ) do_expr expr locn
+
+ ExprStmtOut expr locn a b ->
+ do_expr expr locn `thenDs` \ expr2 ->
+ ds_rest `thenDs` \ rest ->
+ newSysLocalDs a `thenDs` \ ignored_result_id ->
+ dsApp (HsVar then_id) [TyArg a, TyArg b, VarArg expr2,
+ VarArg (mkValLam [ignored_result_id] rest)]
+
+ LetStmt binds ->
+ dsBinds False binds `thenDs` \ binds2 ->
+ ds_rest `thenDs` \ rest ->
+ returnDs (mkCoLetsAny binds2 rest)
+
+ BindStmtOut pat expr locn a b ->
+ do_expr expr locn `thenDs` \ expr2 ->
+ let
+ zero_expr = TyApp (HsVar zero_id) [b]
+ main_match
+ = PatMatch pat (SimpleMatch (HsDoOut stmts then_id zero_id locn))
+ the_matches
+ = if failureFreePat pat
+ then [main_match]
+ else [main_match, PatMatch (WildPat a) (SimpleMatch zero_expr)]
+ in
+ matchWrapper DoBindMatch the_matches "`do' statement"
+ `thenDs` \ (binders, matching_code) ->
+ dsApp (HsVar then_id) [TyArg a, TyArg b,
+ VarArg expr2, VarArg (mkValLam binders matching_code)]
+ where
+ ds_rest = dsDo then_id zero_id stmts
+ do_expr expr locn = putSrcLocDs locn (dsExpr expr)
+
+#ifdef DEBUG
+dsDo then_expr zero_expr [] = panic "dsDo:[]"
+#endif
\end{code}
projects / ghc-hetmet.git / blobdiff