+%
+% (c) The GRASP/AQUA Project, Glasgow University, 1998
+%
+\section[Type]{Type}
+
\begin{code}
module Type (
- Type(..), TyNote(..), -- Representation visible to friends
+ Type(..), TyNote(..), UsageAnn(..), -- Representation visible to friends
Kind, TyVarSubst,
superKind, superBoxity, -- :: SuperKind
mkAppTy, mkAppTys, splitAppTy, splitAppTys, splitAppTy_maybe,
- mkFunTy, mkFunTys, splitFunTy_maybe, splitFunTys, funResultTy,
+ mkFunTy, mkFunTys, splitFunTy_maybe, splitFunTys, splitFunTysN, funResultTy,
zipFunTys,
mkTyConApp, mkTyConTy, splitTyConApp_maybe,
- splitAlgTyConApp_maybe, splitAlgTyConApp,
+ splitAlgTyConApp_maybe, splitAlgTyConApp, splitRepTyConApp_maybe,
mkDictTy, splitDictTy_maybe, isDictTy,
- mkSynTy, isSynTy,
+ mkSynTy, isSynTy, deNoteType,
+
+ mkUsgTy, isUsgTy{- dont use -}, isNotUsgTy, splitUsgTy, unUsgTy, tyUsg,
mkForAllTy, mkForAllTys, splitForAllTy_maybe, splitForAllTys,
- applyTy, applyTys, isForAllTy,
- mkPiType,
+ isForAllTy, applyTy, applyTys, mkPiType,
TauType, RhoType, SigmaType, ThetaType,
isTauTy,
mkSigmaTy, splitSigmaTy,
-- Lifting and boxity
- isUnLiftedType, isUnboxedType, isUnboxedTupleType, isAlgType,
+ isUnLiftedType, isUnboxedType, isUnboxedTupleType, isAlgType, isDataType,
typePrimRep,
-- Free variables
tyVarsOfType, tyVarsOfTypes, namesOfType, typeKind,
addFreeTyVars,
- -- Substitution
- substTy, substTheta, fullSubstTy, substTyVar,
- substTopTy, substTopTheta,
-
-- Tidying up for printing
tidyType, tidyTypes,
tidyOpenType, tidyOpenTypes,
#include "HsVersions.h"
-import {-# SOURCE #-} DataCon( DataCon )
+import {-# SOURCE #-} DataCon( DataCon, dataConType )
import {-# SOURCE #-} PprType( pprType ) -- Only called in debug messages
+import {-# SOURCE #-} Subst ( mkTyVarSubst, substTy )
-- friends:
-import Var ( Id, TyVar, IdOrTyVar,
- tyVarKind, isId, idType, setVarOcc
+import Var ( Id, TyVar, IdOrTyVar, UVar,
+ tyVarKind, tyVarName, isId, idType, setTyVarName, setVarOcc
)
import VarEnv
import VarSet
import Name ( NamedThing(..), Provenance(..), ExportFlag(..),
- mkWiredInTyConName, mkGlobalName, tcOcc,
+ mkWiredInTyConName, mkGlobalName, mkLocalName, mkKindOccFS, tcName,
tidyOccName, TidyOccEnv
)
import NameSet
import TyCon ( TyCon, KindCon,
mkFunTyCon, mkKindCon, mkSuperKindCon,
matchesTyCon, isUnboxedTupleTyCon, isUnLiftedTyCon,
- isFunTyCon,
+ isFunTyCon, isDataTyCon, isNewTyCon,
isAlgTyCon, isSynTyCon, tyConArity,
tyConKind, tyConDataCons, getSynTyConDefn,
tyConPrimRep, tyConClass_maybe
-- others
import BasicTypes ( Unused )
-import SrcLoc ( mkBuiltinSrcLoc )
+import SrcLoc ( mkBuiltinSrcLoc, noSrcLoc )
import PrelMods ( pREL_GHC )
import Maybes ( maybeToBool )
import PrimRep ( PrimRep(..), isFollowableRep )
import Unique -- quite a few *Keys
-import Util ( thenCmp, mapAccumL )
+import Util ( thenCmp, mapAccumL, seqList, ($!) )
import Outputable
\end{code}
A type is
*unboxed* iff its representation is other than a pointer
- Unboxed types cannot instantiate a type variable
+ Unboxed types cannot instantiate a type variable.
Unboxed types are always unlifted.
*lifted* A type is lifted iff it has bottom as an element.
can be entered.
(NOTE: previously "pointed").
- *algebraic* A type with one or more constructors. An algebraic
- type is one that can be deconstructed with a case
- expression. *NOT* the same as lifted types,
- because we also include unboxed tuples in this
- classification.
+ *algebraic* A type with one or more constructors, whether declared
+ with "data" or "newtype".
+ An algebraic type is one that can be deconstructed
+ with a case expression.
+ *NOT* the same as lifted types, because we also
+ include unboxed tuples in this classification.
+
+ *data* A type declared with "data". Also boxed tuples.
*primitive* iff it is a built-in type that can't be expressed
in Haskell.
type SuperKind = Type
type Kind = Type
-type TyVarSubst = TyVarEnv Type
+type TyVarSubst = TyVarEnv Type
data Type
= TyVarTy TyVar
data TyNote
= SynNote Type -- The unexpanded version of the type synonym; always a TyConApp
| FTVNote TyVarSet -- The free type variables of the noted expression
+ | UsgNote UsageAnn -- The usage annotation at this node
+
+data UsageAnn
+ = UsOnce -- Used at most once
+ | UsMany -- Used possibly many times (no info; this annotation can be omitted)
+ | UsVar UVar -- Annotation is variable (should only happen inside analysis)
\end{code}
| sk -> sk -- In ptic (BX -> KX)
\begin{code}
-mk_kind_name key str = mkGlobalName key pREL_GHC (tcOcc str)
+mk_kind_name key str = mkGlobalName key pREL_GHC (mkKindOccFS tcName str)
(LocalDef mkBuiltinSrcLoc NotExported)
-- mk_kind_name is a bit of a hack
-- The LocalDef means that we print the name without
We define a few wired-in type constructors here to avoid module knots
\begin{code}
-funTyConName = mkWiredInTyConName funTyConKey pREL_GHC SLIT("->") funTyCon
+funTyConName = mkWiredInTyConName funTyConKey pREL_GHC SLIT("(->)") funTyCon
funTyCon = mkFunTyCon funTyConName (mkArrowKinds [boxedTypeKind, boxedTypeKind] boxedTypeKind)
\end{code}
invariant: use it.
\begin{code}
-mkAppTy orig_ty1 orig_ty2 = mk_app orig_ty1
+mkAppTy orig_ty1 orig_ty2 = ASSERT2( isNotUsgTy orig_ty1 && isNotUsgTy orig_ty2, pprType orig_ty1 <+> text "to" <+> pprType orig_ty2 )
+ mk_app orig_ty1
where
mk_app (NoteTy _ ty1) = mk_app ty1
mk_app (TyConApp tc tys) = mkTyConApp tc (tys ++ [orig_ty2])
-- For example: mkAppTys Rational []
-- returns to (Ratio Integer), which has needlessly lost
-- the Rational part.
-mkAppTys orig_ty1 orig_tys2 = mk_app orig_ty1
+mkAppTys orig_ty1 orig_tys2 = ASSERT2( isNotUsgTy orig_ty1, pprType orig_ty1 )
+ mk_app orig_ty1
where
mk_app (NoteTy _ ty1) = mk_app ty1
mk_app (TyConApp tc tys) = mkTyConApp tc (tys ++ orig_tys2)
- mk_app ty1 = foldl AppTy orig_ty1 orig_tys2
+ mk_app ty1 = ASSERT2( all isNotUsgTy orig_tys2, pprType orig_ty1 <+> text "to" <+> hsep (map pprType orig_tys2) )
+ foldl AppTy orig_ty1 orig_tys2
splitAppTy_maybe :: Type -> Maybe (Type, Type)
splitAppTy_maybe (FunTy ty1 ty2) = Just (TyConApp funTyCon [ty1], ty2)
splitFunTy_maybe (NoteTy _ ty) = splitFunTy_maybe ty
splitFunTy_maybe other = Nothing
-
splitFunTys :: Type -> ([Type], Type)
splitFunTys ty = split [] ty ty
where
split args orig_ty (NoteTy _ ty) = split args orig_ty ty
split args orig_ty ty = (reverse args, orig_ty)
+splitFunTysN :: String -> Int -> Type -> ([Type], Type)
+splitFunTysN msg orig_n orig_ty = split orig_n [] orig_ty orig_ty
+ where
+ split 0 args syn_ty ty = (reverse args, syn_ty)
+ split n args syn_ty (FunTy arg res) = split (n-1) (arg:args) res res
+ split n args syn_ty (NoteTy _ ty) = split n args syn_ty ty
+ split n args syn_ty ty = pprPanic ("splitFunTysN: " ++ msg) (int orig_n <+> pprType orig_ty)
+
zipFunTys :: Outputable a => [a] -> Type -> ([(a,Type)], Type)
zipFunTys orig_xs orig_ty = split [] orig_xs orig_ty orig_ty
where
\end{code}
-
---------------------------------------------------------------------
TyConApp
~~~~~~~~
isDictTy other = False
\end{code}
+splitRepTyConApp_maybe is like splitTyConApp_maybe except
+that it looks through
+ (a) for-alls, and
+ (b) newtypes
+in addition to synonyms. It's useful in the back end where we're not
+interested in newtypes anymore.
+
+\begin{code}
+splitRepTyConApp_maybe :: Type -> Maybe (TyCon, [Type])
+splitRepTyConApp_maybe (FunTy arg res) = Just (funTyCon, [arg,res])
+splitRepTyConApp_maybe (NoteTy _ ty) = splitRepTyConApp_maybe ty
+splitRepTyConApp_maybe (ForAllTy _ ty) = splitRepTyConApp_maybe ty
+splitRepTyConApp_maybe (TyConApp tc tys)
+ | isNewTyCon tc
+ = case splitFunTy_maybe (applyTys (dataConType (head (tyConDataCons tc))) tys) of
+ Just (rep_ty, _) -> splitRepTyConApp_maybe rep_ty
+ | otherwise
+ = Just (tc,tys)
+splitRepTyConApp_maybe other = Nothing
+\end{code}
---------------------------------------------------------------------
SynTy
\begin{code}
mkSynTy syn_tycon tys
- = ASSERT(isSynTyCon syn_tycon)
+ = ASSERT( isSynTyCon syn_tycon )
+ ASSERT( isNotUsgTy body )
NoteTy (SynNote (TyConApp syn_tycon tys))
- (substTopTy (zipVarEnv tyvars tys) body)
+ (substTy (mkTyVarSubst tyvars tys) body)
where
(tyvars, body) = getSynTyConDefn syn_tycon
isSynTy (NoteTy (SynNote _) _) = True
isSynTy other = False
+
+deNoteType :: Type -> Type
+ -- Sorry for the cute name
+deNoteType ty@(TyVarTy tyvar) = ty
+deNoteType (TyConApp tycon tys) = TyConApp tycon (map deNoteType tys)
+deNoteType (NoteTy _ ty) = deNoteType ty
+deNoteType (AppTy fun arg) = AppTy (deNoteType fun) (deNoteType arg)
+deNoteType (FunTy fun arg) = FunTy (deNoteType fun) (deNoteType arg)
+deNoteType (ForAllTy tv ty) = ForAllTy tv (deNoteType ty)
\end{code}
Notes on type synonyms
---------------------------------------------------------------------
+ UsgNote
+ ~~~~~~~
+
+NB: Invariant: if present, usage note is at the very top of the type.
+This should be carefully preserved.
+
+In some parts of the compiler, comments use the _Once Upon a
+Polymorphic Type_ (POPL'99) usage of "sigma = usage-annotated type;
+tau = un-usage-annotated type"; unfortunately this conflicts with the
+rho/tau/theta/sigma usage in the rest of the compiler.
+(KSW 1999-04)
+
+\begin{code}
+mkUsgTy :: UsageAnn -> Type -> Type
+#ifndef USMANY
+mkUsgTy UsMany ty = ASSERT2( isNotUsgTy ty, pprType ty )
+ ty
+#endif
+mkUsgTy usg ty = ASSERT2( isNotUsgTy ty, pprType ty )
+ NoteTy (UsgNote usg) ty
+
+-- The isUsgTy function is utterly useless if UsManys are omitted.
+-- Be warned! KSW 1999-04.
+isUsgTy :: Type -> Bool
+#ifndef USMANY
+isUsgTy _ = True
+#else
+isUsgTy (NoteTy (UsgNote _) _) = True
+isUsgTy other = False
+#endif
+
+-- The isNotUsgTy function may return a false True if UsManys are omitted;
+-- in other words, A SSERT( isNotUsgTy ty ) may be useful but
+-- A SSERT( not (isNotUsg ty) ) is asking for trouble. KSW 1999-04.
+isNotUsgTy :: Type -> Bool
+isNotUsgTy (NoteTy (UsgNote _) _) = False
+isNotUsgTy other = True
+
+-- splitUsgTy_maybe is not exported, since it is meaningless if
+-- UsManys are omitted. It is used in several places in this module,
+-- however. KSW 1999-04.
+splitUsgTy_maybe :: Type -> Maybe (UsageAnn,Type)
+splitUsgTy_maybe (NoteTy (UsgNote usg) ty2) = ASSERT( isNotUsgTy ty2 )
+ Just (usg,ty2)
+splitUsgTy_maybe ty = Nothing
+
+splitUsgTy :: Type -> (UsageAnn,Type)
+splitUsgTy ty = case splitUsgTy_maybe ty of
+ Just ans -> ans
+ Nothing ->
+#ifndef USMANY
+ (UsMany,ty)
+#else
+ pprPanic "splitUsgTy: no usage annot:" $ pprType ty
+#endif
+
+tyUsg :: Type -> UsageAnn
+tyUsg = fst . splitUsgTy
+
+unUsgTy :: Type -> Type
+-- strip outer usage annotation if present
+unUsgTy ty = case splitUsgTy_maybe ty of
+ Just (_,ty1) -> ASSERT2( isNotUsgTy ty1, pprType ty )
+ ty1
+ Nothing -> ty
+\end{code}
+
+
+
+---------------------------------------------------------------------
ForAllTy
~~~~~~~~
+We need to be clever here with usage annotations; they need to be
+lifted or lowered through the forall as appropriate.
+
\begin{code}
-mkForAllTy = ForAllTy
+mkForAllTy :: TyVar -> Type -> Type
+mkForAllTy tyvar ty = case splitUsgTy_maybe ty of
+ Just (usg,ty') -> NoteTy (UsgNote usg)
+ (ForAllTy tyvar ty')
+ Nothing -> ForAllTy tyvar ty
mkForAllTys :: [TyVar] -> Type -> Type
-mkForAllTys tyvars ty = foldr ForAllTy ty tyvars
+mkForAllTys tyvars ty = case splitUsgTy_maybe ty of
+ Just (usg,ty') -> NoteTy (UsgNote usg)
+ (foldr ForAllTy ty' tyvars)
+ Nothing -> foldr ForAllTy ty tyvars
splitForAllTy_maybe :: Type -> Maybe (TyVar, Type)
-splitForAllTy_maybe (NoteTy _ ty) = splitForAllTy_maybe ty
-splitForAllTy_maybe (ForAllTy tyvar ty) = Just(tyvar, ty)
-splitForAllTy_maybe _ = Nothing
+splitForAllTy_maybe ty = case splitUsgTy_maybe ty of
+ Just (usg,ty') -> do (tyvar,ty'') <- splitFAT_m ty'
+ return (tyvar, NoteTy (UsgNote usg) ty'')
+ Nothing -> splitFAT_m ty
+ where
+ splitFAT_m (NoteTy _ ty) = splitFAT_m ty
+ splitFAT_m (ForAllTy tyvar ty) = Just(tyvar, ty)
+ splitFAT_m _ = Nothing
isForAllTy :: Type -> Bool
isForAllTy (NoteTy _ ty) = isForAllTy ty
isForAllTy _ = False
splitForAllTys :: Type -> ([TyVar], Type)
-splitForAllTys ty = split ty ty []
+splitForAllTys ty = case splitUsgTy_maybe ty of
+ Just (usg,ty') -> let (tvs,ty'') = split ty' ty' []
+ in (tvs, NoteTy (UsgNote usg) ty'')
+ Nothing -> split ty ty []
where
split orig_ty (ForAllTy tv ty) tvs = split ty ty (tv:tvs)
split orig_ty (NoteTy _ ty) tvs = split orig_ty ty tvs
\begin{code}
mkPiType :: IdOrTyVar -> Type -> Type -- The more polymorphic version doesn't work...
mkPiType v ty | isId v = mkFunTy (idType v) ty
- | otherwise = ForAllTy v ty
+ | otherwise = mkForAllTy v ty
\end{code}
+Applying a for-all to its arguments
+
\begin{code}
applyTy :: Type -> Type -> Type
-applyTy (NoteTy _ fun) arg = applyTy fun arg
-applyTy (ForAllTy tv ty) arg = substTy (mkVarEnv [(tv,arg)]) ty
-applyTy other arg = panic "applyTy"
+applyTy (NoteTy note@(UsgNote _) fun) arg = NoteTy note (applyTy fun arg)
+applyTy (NoteTy _ fun) arg = applyTy fun arg
+applyTy (ForAllTy tv ty) arg = ASSERT( isNotUsgTy arg )
+ substTy (mkTyVarSubst [tv] [arg]) ty
+applyTy other arg = panic "applyTy"
applyTys :: Type -> [Type] -> Type
applyTys fun_ty arg_tys
- = go [] fun_ty arg_tys
+ = substTy (mkTyVarSubst tvs arg_tys) ty
where
+ (tvs, ty) = split fun_ty arg_tys
+
+ split fun_ty [] = ([], fun_ty)
+ split (NoteTy _ fun_ty) args = split fun_ty args
+ split (ForAllTy tv fun_ty) (arg:args) = ASSERT2( isNotUsgTy arg, vcat (map pprType arg_tys) $$
+ text "in application of" <+> pprType fun_ty)
+ case split fun_ty args of
+ (tvs, ty) -> (tv:tvs, ty)
+ split other_ty args = panic "applyTys"
+
+{- OLD version with bogus usage stuff
+
+ ************* CHECK WITH KEITH **************
+
go env ty [] = substTy (mkVarEnv env) ty
+ go env (NoteTy note@(UsgNote _) fun)
+ args = NoteTy note (go env fun args)
go env (NoteTy _ fun) args = go env fun args
go env (ForAllTy tv ty) (arg:args) = go ((tv,arg):env) ty args
go env other args = panic "applyTys"
+-}
\end{code}
+Note that we allow applications to be of usage-annotated- types, as an
+extension: we handle them by lifting the annotation outside. The
+argument, however, must still be unannotated.
%************************************************************************
%* *
typeKind (TyConApp tycon tys) = foldr (\_ k -> funResultTy k) (tyConKind tycon) tys
typeKind (NoteTy _ ty) = typeKind ty
typeKind (AppTy fun arg) = funResultTy (typeKind fun)
-typeKind (FunTy fun arg) = typeKindF arg
-typeKind (ForAllTy _ ty) = typeKindF ty -- We could make this a new kind polyTypeKind
- -- to prevent a forall type unifying with a
- -- boxed type variable, but I didn't think it
- -- was worth it yet.
-
--- The complication is that a *function* is boxed even if
--- its *result* type is unboxed. Seems wierd.
-
-typeKindF :: Type -> Kind
-typeKindF (NoteTy _ ty) = typeKindF ty
-typeKindF (FunTy _ ty) = typeKindF ty
-typeKindF (ForAllTy _ ty) = typeKindF ty
-typeKindF other = fix_up (typeKind other)
- where
- fix_up (TyConApp kc _) | kc == typeCon = boxedTypeKind
- -- Functions at the type level are always boxed
- fix_up (NoteTy _ kind) = fix_up kind
- fix_up kind = kind
+
+typeKind (FunTy arg res) = boxedTypeKind -- A function is boxed regardless of its result type
+ -- No functions at the type level, hence we don't need
+ -- to say (typeKind res).
+
+typeKind (ForAllTy tv ty) = typeKind ty
\end{code}
tyVarsOfType (TyConApp tycon tys) = tyVarsOfTypes tys
tyVarsOfType (NoteTy (FTVNote tvs) ty2) = tvs
tyVarsOfType (NoteTy (SynNote ty1) ty2) = tyVarsOfType ty1
+tyVarsOfType (NoteTy (UsgNote _) ty) = tyVarsOfType ty
tyVarsOfType (FunTy arg res) = tyVarsOfType arg `unionVarSet` tyVarsOfType res
tyVarsOfType (AppTy fun arg) = tyVarsOfType fun `unionVarSet` tyVarsOfType arg
tyVarsOfType (ForAllTy tyvar ty) = tyVarsOfType ty `minusVarSet` unitVarSet tyvar
tyVarsOfTypes tys = foldr (unionVarSet.tyVarsOfType) emptyVarSet tys
-- Add a Note with the free tyvars to the top of the type
+-- (but under a usage if there is one)
addFreeTyVars :: Type -> Type
-addFreeTyVars ty@(NoteTy (FTVNote _) _) = ty
-addFreeTyVars ty = NoteTy (FTVNote (tyVarsOfType ty)) ty
+addFreeTyVars (NoteTy note@(UsgNote _) ty) = NoteTy note (addFreeTyVars ty)
+addFreeTyVars ty@(NoteTy (FTVNote _) _) = ty
+addFreeTyVars ty = NoteTy (FTVNote (tyVarsOfType ty)) ty
-- Find the free names of a type, including the type constructors and classes it mentions
namesOfType :: Type -> NameSet
%************************************************************************
%* *
-\subsection{Instantiating a type}
-%* *
-%************************************************************************
-
-@substTy@ applies a substitution to a type. It deals correctly with name capture.
-
-\begin{code}
-substTy :: TyVarSubst -> Type -> Type
-substTy tenv ty
- | isEmptyVarEnv tenv = ty
- | otherwise = subst_ty tenv tset ty
- where
- tset = foldVarEnv (unionVarSet . tyVarsOfType) emptyVarSet tenv
- -- If ty doesn't have any for-alls, then this thunk
- -- will never be evaluated
-
-substTheta :: TyVarSubst -> ThetaType -> ThetaType
-substTheta tenv theta
- | isEmptyVarEnv tenv = theta
- | otherwise = [(clas, map (subst_ty tenv tset) tys) | (clas, tys) <- theta]
- where
- tset = foldVarEnv (unionVarSet . tyVarsOfType) emptyVarSet tenv
- -- If ty doesn't have any for-alls, then this thunk
- -- will never be evaluated
-
-substTopTy :: TyVarSubst -> Type -> Type
-substTopTy = substTy -- Called when doing top-level substitutions.
- -- Here we expect that the free vars of the range of the
- -- substitution will be empty; but during typechecking I'm
- -- a bit dubious about that (mutable tyvars bouund to Int, say)
- -- So I've left it as substTy for the moment. SLPJ Nov 98
-substTopTheta = substTheta
-\end{code}
-
-@fullSubstTy@ is like @substTy@ except that it needs to be given a set
-of in-scope type variables. In exchange it's a bit more efficient, at least
-if you happen to have that set lying around.
-
-\begin{code}
-fullSubstTy :: TyVarSubst -- Substitution to apply
- -> TyVarSet -- Superset of the free tyvars of
- -- the range of the tyvar env
- -> Type -> Type
--- ASSUMPTION: The substitution is idempotent.
--- Equivalently: No tyvar is both in scope, and in the domain of the substitution.
-fullSubstTy tenv tset ty | isEmptyVarEnv tenv = ty
- | otherwise = subst_ty tenv tset ty
-
--- subst_ty does the business
-subst_ty tenv tset ty
- = go ty
- where
- go (TyConApp tc tys) = TyConApp tc (map go tys)
- go (NoteTy (SynNote ty1) ty2) = NoteTy (SynNote (go ty1)) (go ty2)
- go (NoteTy (FTVNote _) ty2) = go ty2 -- Discard the free tyvar note
- go (FunTy arg res) = FunTy (go arg) (go res)
- go (AppTy fun arg) = mkAppTy (go fun) (go arg)
- go ty@(TyVarTy tv) = case (lookupVarEnv tenv tv) of
- Nothing -> ty
- Just ty' -> ty'
- go (ForAllTy tv ty) = case substTyVar tenv tset tv of
- (tenv', tset', tv') -> ForAllTy tv' (subst_ty tenv' tset' ty)
-
-substTyVar :: TyVarSubst -> TyVarSet -> TyVar
- -> (TyVarSubst, TyVarSet, TyVar)
-
-substTyVar tenv tset tv
- | not (tv `elemVarSet` tset) -- No need to clone
- -- But must delete from substitution
- = (tenv `delVarEnv` tv, tset `extendVarSet` tv, tv)
-
- | otherwise -- The forall's variable is in scope so
- -- we'd better rename it away from the in-scope variables
- -- Extending the substitution to do this renaming also
- -- has the (correct) effect of discarding any existing
- -- substitution for that variable
- = (extendVarEnv tenv tv (TyVarTy tv'), tset `extendVarSet` tv', tv')
- where
- tv' = uniqAway tset tv
-\end{code}
-
-
-%************************************************************************
-%* *
\subsection{TidyType}
%* *
%************************************************************************
Nothing -> -- Make a new nice name for it
- case tidyOccName tidy_env (getOccName tyvar) of
+ case tidyOccName tidy_env (getOccName name) of
(tidy', occ') -> -- New occname reqd
((tidy', subst'), tyvar')
where
subst' = extendVarEnv subst tyvar tyvar'
- tyvar' = setVarOcc tyvar occ'
+ tyvar' = setTyVarName tyvar name'
+ name' = mkLocalName (getUnique name) occ' noSrcLoc
+ -- Note: make a *user* tyvar, so it printes nicely
+ -- Could extract src loc, but no need.
+ where
+ name = tyVarName tyvar
tidyTyVars env tyvars = mapAccumL tidyTyVar env tyvars
go (TyVarTy tv) = case lookupVarEnv subst tv of
Nothing -> TyVarTy tv
Just tv' -> TyVarTy tv'
- go (TyConApp tycon tys) = TyConApp tycon (map go tys)
- go (NoteTy note ty) = NoteTy (go_note note) (go ty)
- go (AppTy fun arg) = AppTy (go fun) (go arg)
- go (FunTy fun arg) = FunTy (go fun) (go arg)
- go (ForAllTy tv ty) = ForAllTy tv' (tidyType env' ty)
+ go (TyConApp tycon tys) = let args = map go tys
+ in args `seqList` TyConApp tycon args
+ go (NoteTy note ty) = (NoteTy $! (go_note note)) $! (go ty)
+ go (AppTy fun arg) = (AppTy $! (go fun)) $! (go arg)
+ go (FunTy fun arg) = (FunTy $! (go fun)) $! (go arg)
+ go (ForAllTy tv ty) = ForAllTy tv' $! (tidyType env' ty)
where
(env', tv') = tidyTyVar env tv
- go_note (SynNote ty) = SynNote (go ty)
+ go_note (SynNote ty) = SynNote $! (go ty)
go_note note@(FTVNote ftvs) = note -- No need to tidy the free tyvars
+ go_note note@(UsgNote _) = note -- Usage annotation is already tidy
tidyTypes env tys = map (tidyType env) tys
\end{code}
Just (tc, ty_args) -> isUnboxedTupleTyCon tc
other -> False
+-- Should only be applied to *types*; hence the assert
isAlgType :: Type -> Bool
isAlgType ty = case splitTyConApp_maybe ty of
- Just (tc, ty_args) -> isAlgTyCon tc
+ Just (tc, ty_args) -> ASSERT( length ty_args == tyConArity tc )
+ isAlgTyCon tc
+ other -> False
+
+-- Should only be applied to *types*; hence the assert
+isDataType :: Type -> Bool
+isDataType ty = case splitTyConApp_maybe ty of
+ Just (tc, ty_args) -> ASSERT( length ty_args == tyConArity tc )
+ isDataTyCon tc
other -> False
typePrimRep :: Type -> PrimRep
projects / ghc-hetmet.git / blobdiff