X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fprelude%2FTysPrim.lhs;h=a5d93350bb4c1fc2bc16e839c3e2e390145c4954;hp=056c5e47fd5bbac7eb111a59cf791f196ca7226e;hb=16b9e80dc14db24509f051f294b5b51943285090;hpb=e464bf29ba109c7100e5747ac9735871c7d2b710 diff --git a/compiler/prelude/TysPrim.lhs b/compiler/prelude/TysPrim.lhs index 056c5e4..a5d9335 100644 --- a/compiler/prelude/TysPrim.lhs +++ b/compiler/prelude/TysPrim.lhs @@ -1,20 +1,18 @@ % % (c) The AQUA Project, Glasgow University, 1994-1998 % + + \section[TysPrim]{Wired-in knowledge about primitive types} \begin{code} -{-# OPTIONS -w #-} --- The above warning supression flag is a temporary kludge. --- While working on this module you are encouraged to remove it and fix --- any warnings in the module. See --- http://hackage.haskell.org/trac/ghc/wiki/Commentary/CodingStyle#Warnings --- for details - +-- | This module defines TyCons that can't be expressed in Haskell. +-- They are all, therefore, wired-in TyCons. C.f module TysWiredIn module TysPrim( alphaTyVars, betaTyVars, alphaTyVar, betaTyVar, gammaTyVar, deltaTyVar, - alphaTy, betaTy, gammaTy, deltaTy, + alphaTy, betaTy, gammaTy, deltaTy, ecTyVars, openAlphaTy, openBetaTy, openAlphaTyVar, openBetaTyVar, openAlphaTyVars, + argAlphaTy, argAlphaTyVar, argBetaTy, argBetaTyVar, primTyCons, @@ -48,30 +46,27 @@ module TysPrim( int64PrimTyCon, int64PrimTy, word64PrimTyCon, word64PrimTy, - anyPrimTyCon, anyPrimTy, anyPrimTyCon1, mkAnyPrimTyCon + -- * Any + anyTyCon, anyTyConOfKind, anyTypeOfKind ) where #include "HsVersions.h" import Var ( TyVar, mkTyVar ) import Name ( Name, BuiltInSyntax(..), mkInternalName, mkWiredInName ) -import OccName ( mkOccNameFS, tcName, mkTyVarOcc ) -import TyCon ( TyCon, mkPrimTyCon, mkLiftedPrimTyCon, - PrimRep(..) ) -import Type ( mkTyConApp, mkTyConTy, mkTyVarTys, mkTyVarTy, - unliftedTypeKind, - liftedTypeKind, openTypeKind, - Kind, mkArrowKinds, mkArrowKind, - TyThing(..) - ) +import OccName ( mkTcOcc ) +import OccName ( mkTyVarOccFS, mkTcOccFS ) +import TyCon ( TyCon, mkPrimTyCon, mkLiftedPrimTyCon, mkAnyTyCon ) +import Type +import TypeRep ( ecKind ) +import Coercion import SrcLoc -import Unique ( mkAlphaTyVarUnique, pprUnique ) +import Unique ( mkAlphaTyVarUnique ) import PrelNames -import StaticFlags import FastString import Outputable -import Char ( ord, chr ) +import Data.Char \end{code} %************************************************************************ @@ -107,16 +102,17 @@ primTyCons , wordPrimTyCon , word32PrimTyCon , word64PrimTyCon - , anyPrimTyCon, anyPrimTyCon1 + , anyTyCon ] mkPrimTc :: FastString -> Unique -> TyCon -> Name -mkPrimTc fs uniq tycon - = mkWiredInName gHC_PRIM (mkOccNameFS tcName fs) - uniq +mkPrimTc fs unique tycon + = mkWiredInName gHC_PRIM (mkTcOccFS fs) + unique (ATyCon tycon) -- Relevant TyCon UserSyntax -- None are built-in syntax +charPrimTyConName, intPrimTyConName, int32PrimTyConName, int64PrimTyConName, wordPrimTyConName, word32PrimTyConName, word64PrimTyConName, addrPrimTyConName, floatPrimTyConName, doublePrimTyConName, statePrimTyConName, realWorldTyConName, arrayPrimTyConName, byteArrayPrimTyConName, mutableArrayPrimTyConName, mutableByteArrayPrimTyConName, mutVarPrimTyConName, mVarPrimTyConName, tVarPrimTyConName, stablePtrPrimTyConName, stableNamePrimTyConName, bcoPrimTyConName, weakPrimTyConName, threadIdPrimTyConName :: Name charPrimTyConName = mkPrimTc (fsLit "Char#") charPrimTyConKey charPrimTyCon intPrimTyConName = mkPrimTc (fsLit "Int#") intPrimTyConKey intPrimTyCon int32PrimTyConName = mkPrimTc (fsLit "Int32#") int32PrimTyConKey int32PrimTyCon @@ -141,8 +137,6 @@ stableNamePrimTyConName = mkPrimTc (fsLit "StableName#") stableNamePrimTyC bcoPrimTyConName = mkPrimTc (fsLit "BCO#") bcoPrimTyConKey bcoPrimTyCon weakPrimTyConName = mkPrimTc (fsLit "Weak#") weakPrimTyConKey weakPrimTyCon threadIdPrimTyConName = mkPrimTc (fsLit "ThreadId#") threadIdPrimTyConKey threadIdPrimTyCon -anyPrimTyConName = mkPrimTc (fsLit "Any") anyPrimTyConKey anyPrimTyCon -anyPrimTyCon1Name = mkPrimTc (fsLit "Any1") anyPrimTyCon1Key anyPrimTyCon \end{code} %************************************************************************ @@ -157,7 +151,7 @@ alphaTyVars is a list of type variables for use in templates: \begin{code} tyVarList :: Kind -> [TyVar] tyVarList kind = [ mkTyVar (mkInternalName (mkAlphaTyVarUnique u) - (mkTyVarOcc (mkFastString name)) + (mkTyVarOccFS (mkFastString name)) noSrcSpan) kind | u <- [2..], let name | c <= 'z' = [c] @@ -165,25 +159,145 @@ tyVarList kind = [ mkTyVar (mkInternalName (mkAlphaTyVarUnique u) where c = chr (u-2 + ord 'a') ] +ecTyVars :: [TyVar] +ecTyVars = tyVarList ecKind + alphaTyVars :: [TyVar] alphaTyVars = tyVarList liftedTypeKind +betaTyVars :: [TyVar] betaTyVars = tail alphaTyVars -alphaTyVar, betaTyVar, gammaTyVar :: TyVar +alphaTyVar, betaTyVar, gammaTyVar, deltaTyVar :: TyVar (alphaTyVar:betaTyVar:gammaTyVar:deltaTyVar:_) = alphaTyVars +alphaTys :: [Type] alphaTys = mkTyVarTys alphaTyVars +alphaTy, betaTy, gammaTy, deltaTy :: Type (alphaTy:betaTy:gammaTy:deltaTy:_) = alphaTys -- openAlphaTyVar is prepared to be instantiated -- to a lifted or unlifted type variable. It's used for the -- result type for "error", so that we can have (error Int# "Help") openAlphaTyVars :: [TyVar] +openAlphaTyVar, openBetaTyVar :: TyVar openAlphaTyVars@(openAlphaTyVar:openBetaTyVar:_) = tyVarList openTypeKind +openAlphaTy, openBetaTy :: Type openAlphaTy = mkTyVarTy openAlphaTyVar -openBetaTy = mkTyVarTy openBetaTyVar +openBetaTy = mkTyVarTy openBetaTyVar + +argAlphaTyVar, argBetaTyVar :: TyVar +(argAlphaTyVar : argBetaTyVar : _) = tyVarList argTypeKind +argAlphaTy, argBetaTy :: Type +argAlphaTy = mkTyVarTy argAlphaTyVar +argBetaTy = mkTyVarTy argBetaTyVar +\end{code} + + +%************************************************************************ +%* * + Any +%* * +%************************************************************************ + +Note [Any types] +~~~~~~~~~~~~~~~~ +The type constructor Any::* has these properties + + * It is defined in module GHC.Prim, and exported so that it is + available to users. For this reason it's treated like any other + primitive type: + - has a fixed unique, anyTyConKey, + - lives in the global name cache + - built with TyCon.PrimTyCon + + * It is lifted, and hence represented by a pointer + + * It is inhabited by at least one value, namely bottom + + * You can unsafely coerce any lifted type to Ayny, and back. + + * It does not claim to be a *data* type, and that's important for + the code generator, because the code gen may *enter* a data value + but never enters a function value. + + * It is used to instantiate otherwise un-constrained type variables of kind * + For example length Any [] + See Note [Strangely-kinded void TyCons] + +In addition, we have a potentially-infinite family of types, one for +each kind /other than/ *, needed to instantiate otherwise +un-constrained type variables of kinds other than *. This is a bit +like tuples; there is a potentially-infinite family. They have slightly +different characteristics to Any::*: + + * They are built with TyCon.AnyTyCon + * They have non-user-writable names like "Any(*->*)" + * They are not exported by GHC.Prim + * They are uninhabited (of course; not kind *) + * They have a unique derived from their OccName (see Note [Uniques of Any]) + * Their Names do not live in the global name cache + +Note [Uniques of Any] +~~~~~~~~~~~~~~~~~~~~~ +Although Any(*->*), say, doesn't have a binding site, it still needs +to have a Unique. Unlike tuples (which are also an infinite family) +there is no convenient way to index them, so we use the Unique from +their OccName instead. That should be unique, + - both wrt each other, because their strings differ + + - and wrt any other Name, because Names get uniques with + various 'char' tags, but the OccName of Any will + get a Unique built with mkTcOccUnique, which has a particular 'char' + tag; see Unique.mkTcOccUnique! + +Note [Strangely-kinded void TyCons] +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +See Trac #959 for more examples + +When the type checker finds a type variable with no binding, which +means it can be instantiated with an arbitrary type, it usually +instantiates it to Void. Eg. + + length [] +===> + length Any (Nil Any) + +But in really obscure programs, the type variable might have a kind +other than *, so we need to invent a suitably-kinded type. + +This commit uses + Any for kind * + Any(*->*) for kind *->* + etc + +\begin{code} +anyTyConName :: Name +anyTyConName = mkPrimTc (fsLit "Any") anyTyConKey anyTyCon + +anyTyCon :: TyCon +anyTyCon = mkLiftedPrimTyCon anyTyConName liftedTypeKind 0 PtrRep + +anyTypeOfKind :: Kind -> Type +anyTypeOfKind kind = mkTyConApp (anyTyConOfKind kind) [] + +anyTyConOfKind :: Kind -> TyCon +-- Map all superkinds of liftedTypeKind to liftedTypeKind +anyTyConOfKind kind + | liftedTypeKind `isSubKind` kind = anyTyCon + | otherwise = tycon + where + -- Derive the name from the kind, thus: + -- Any(*->*), Any(*->*->*) + -- These are names that can't be written by the user, + -- and are not allocated in the global name cache + str = "Any" ++ showSDoc (pprParendKind kind) + + occ = mkTcOcc str + uniq = getUnique occ -- See Note [Uniques of Any] + name = mkWiredInName gHC_PRIM occ uniq (ATyCon tycon) UserSyntax + tycon = mkAnyTyCon name kind \end{code} @@ -208,34 +322,54 @@ pcPrimTyCon0 name rep where result_kind = unliftedTypeKind +charPrimTy :: Type charPrimTy = mkTyConTy charPrimTyCon +charPrimTyCon :: TyCon charPrimTyCon = pcPrimTyCon0 charPrimTyConName WordRep +intPrimTy :: Type intPrimTy = mkTyConTy intPrimTyCon +intPrimTyCon :: TyCon intPrimTyCon = pcPrimTyCon0 intPrimTyConName IntRep +int32PrimTy :: Type int32PrimTy = mkTyConTy int32PrimTyCon +int32PrimTyCon :: TyCon int32PrimTyCon = pcPrimTyCon0 int32PrimTyConName IntRep +int64PrimTy :: Type int64PrimTy = mkTyConTy int64PrimTyCon +int64PrimTyCon :: TyCon int64PrimTyCon = pcPrimTyCon0 int64PrimTyConName Int64Rep +wordPrimTy :: Type wordPrimTy = mkTyConTy wordPrimTyCon +wordPrimTyCon :: TyCon wordPrimTyCon = pcPrimTyCon0 wordPrimTyConName WordRep +word32PrimTy :: Type word32PrimTy = mkTyConTy word32PrimTyCon +word32PrimTyCon :: TyCon word32PrimTyCon = pcPrimTyCon0 word32PrimTyConName WordRep +word64PrimTy :: Type word64PrimTy = mkTyConTy word64PrimTyCon +word64PrimTyCon :: TyCon word64PrimTyCon = pcPrimTyCon0 word64PrimTyConName Word64Rep +addrPrimTy :: Type addrPrimTy = mkTyConTy addrPrimTyCon +addrPrimTyCon :: TyCon addrPrimTyCon = pcPrimTyCon0 addrPrimTyConName AddrRep +floatPrimTy :: Type floatPrimTy = mkTyConTy floatPrimTyCon +floatPrimTyCon :: TyCon floatPrimTyCon = pcPrimTyCon0 floatPrimTyConName FloatRep +doublePrimTy :: Type doublePrimTy = mkTyConTy doublePrimTyCon +doublePrimTyCon :: TyCon doublePrimTyCon = pcPrimTyCon0 doublePrimTyConName DoubleRep \end{code} @@ -256,7 +390,9 @@ where s is a type variable. The only purpose of the type parameter is to keep different state threads separate. It is represented by nothing at all. \begin{code} +mkStatePrimTy :: Type -> Type mkStatePrimTy ty = mkTyConApp statePrimTyCon [ty] +statePrimTyCon :: TyCon statePrimTyCon = pcPrimTyCon statePrimTyConName 1 VoidRep \end{code} @@ -265,8 +401,11 @@ RealWorld is deeply magical. It is *primitive*, but it is not RealWorld; it's only used in the type system, to parameterise State#. \begin{code} +realWorldTyCon :: TyCon realWorldTyCon = mkLiftedPrimTyCon realWorldTyConName liftedTypeKind 0 PtrRep +realWorldTy :: Type realWorldTy = mkTyConTy realWorldTyCon +realWorldStatePrimTy :: Type realWorldStatePrimTy = mkStatePrimTy realWorldTy -- State# RealWorld \end{code} @@ -276,66 +415,25 @@ defined in \tr{TysWiredIn.lhs}, not here. %************************************************************************ %* * - Any -%* * -%************************************************************************ - -The type constructor Any is type to which you can unsafely coerce any -lifted type, and back. - - * It is lifted, and hence represented by a pointer - - * It does not claim to be a *data* type, and that's important for - the code generator, because the code gen may *enter* a data value - but never enters a function value. - -It's also used to instantiate un-constrained type variables after type -checking. For example - length Any [] -Annoyingly, we sometimes need Anys of other kinds, such as (*->*) etc. -This is a bit like tuples. We define a couple of useful ones here, -and make others up on the fly. If any of these others end up being exported -into interface files, we'll get a crash; at least until we add interface-file -syntax to support them. - -\begin{code} -anyPrimTy = mkTyConApp anyPrimTyCon [] - -anyPrimTyCon :: TyCon -- Kind * -anyPrimTyCon = mkLiftedPrimTyCon anyPrimTyConName liftedTypeKind 0 PtrRep - -anyPrimTyCon1 :: TyCon -- Kind *->* -anyPrimTyCon1 = mkLiftedPrimTyCon anyPrimTyCon1Name kind 0 PtrRep - where - kind = mkArrowKind liftedTypeKind liftedTypeKind - -mkAnyPrimTyCon :: Unique -> Kind -> TyCon --- Grotesque hack alert: the client gives the unique; so equality won't work -mkAnyPrimTyCon uniq kind - = WARN( opt_PprStyle_Debug, ptext (sLit "Urk! Inventing strangely-kinded Any TyCon:") <+> ppr uniq <+> ppr kind ) - -- See Note [Strangely-kinded void TyCons] in TcHsSyn - tycon - where - name = mkPrimTc (mkFastString ("Any" ++ showSDoc (pprUnique uniq))) uniq tycon - tycon = mkLiftedPrimTyCon name kind 0 PtrRep -\end{code} - - -%************************************************************************ -%* * \subsection[TysPrim-arrays]{The primitive array types} %* * %************************************************************************ \begin{code} +arrayPrimTyCon, mutableArrayPrimTyCon, mutableByteArrayPrimTyCon, + byteArrayPrimTyCon :: TyCon arrayPrimTyCon = pcPrimTyCon arrayPrimTyConName 1 PtrRep mutableArrayPrimTyCon = pcPrimTyCon mutableArrayPrimTyConName 2 PtrRep mutableByteArrayPrimTyCon = pcPrimTyCon mutableByteArrayPrimTyConName 1 PtrRep byteArrayPrimTyCon = pcPrimTyCon0 byteArrayPrimTyConName PtrRep +mkArrayPrimTy :: Type -> Type mkArrayPrimTy elt = mkTyConApp arrayPrimTyCon [elt] +byteArrayPrimTy :: Type byteArrayPrimTy = mkTyConTy byteArrayPrimTyCon +mkMutableArrayPrimTy :: Type -> Type -> Type mkMutableArrayPrimTy s elt = mkTyConApp mutableArrayPrimTyCon [s, elt] +mkMutableByteArrayPrimTy :: Type -> Type mkMutableByteArrayPrimTy s = mkTyConApp mutableByteArrayPrimTyCon [s] \end{code} @@ -346,8 +444,10 @@ mkMutableByteArrayPrimTy s = mkTyConApp mutableByteArrayPrimTyCon [s] %************************************************************************ \begin{code} +mutVarPrimTyCon :: TyCon mutVarPrimTyCon = pcPrimTyCon mutVarPrimTyConName 2 PtrRep +mkMutVarPrimTy :: Type -> Type -> Type mkMutVarPrimTy s elt = mkTyConApp mutVarPrimTyCon [s, elt] \end{code} @@ -358,8 +458,10 @@ mkMutVarPrimTy s elt = mkTyConApp mutVarPrimTyCon [s, elt] %************************************************************************ \begin{code} +mVarPrimTyCon :: TyCon mVarPrimTyCon = pcPrimTyCon mVarPrimTyConName 2 PtrRep +mkMVarPrimTy :: Type -> Type -> Type mkMVarPrimTy s elt = mkTyConApp mVarPrimTyCon [s, elt] \end{code} @@ -370,9 +472,11 @@ mkMVarPrimTy s elt = mkTyConApp mVarPrimTyCon [s, elt] %************************************************************************ \begin{code} +tVarPrimTyCon :: TyCon tVarPrimTyCon = pcPrimTyCon tVarPrimTyConName 2 PtrRep -mkTVarPrimTy s elt = mkTyConApp tVarPrimTyCon [s, elt] +mkTVarPrimTy :: Type -> Type -> Type +mkTVarPrimTy s elt = mkTyConApp tVarPrimTyCon [s, elt] \end{code} %************************************************************************ @@ -382,8 +486,10 @@ mkTVarPrimTy s elt = mkTyConApp tVarPrimTyCon [s, elt] %************************************************************************ \begin{code} +stablePtrPrimTyCon :: TyCon stablePtrPrimTyCon = pcPrimTyCon stablePtrPrimTyConName 1 AddrRep +mkStablePtrPrimTy :: Type -> Type mkStablePtrPrimTy ty = mkTyConApp stablePtrPrimTyCon [ty] \end{code} @@ -394,8 +500,10 @@ mkStablePtrPrimTy ty = mkTyConApp stablePtrPrimTyCon [ty] %************************************************************************ \begin{code} +stableNamePrimTyCon :: TyCon stableNamePrimTyCon = pcPrimTyCon stableNamePrimTyConName 1 PtrRep +mkStableNamePrimTy :: Type -> Type mkStableNamePrimTy ty = mkTyConApp stableNamePrimTyCon [ty] \end{code} @@ -406,7 +514,9 @@ mkStableNamePrimTy ty = mkTyConApp stableNamePrimTyCon [ty] %************************************************************************ \begin{code} +bcoPrimTy :: Type bcoPrimTy = mkTyConTy bcoPrimTyCon +bcoPrimTyCon :: TyCon bcoPrimTyCon = pcPrimTyCon0 bcoPrimTyConName PtrRep \end{code} @@ -417,8 +527,10 @@ bcoPrimTyCon = pcPrimTyCon0 bcoPrimTyConName PtrRep %************************************************************************ \begin{code} +weakPrimTyCon :: TyCon weakPrimTyCon = pcPrimTyCon weakPrimTyConName 1 PtrRep +mkWeakPrimTy :: Type -> Type mkWeakPrimTy v = mkTyConApp weakPrimTyCon [v] \end{code} @@ -438,6 +550,8 @@ Hence the programmer API for thread manipulation uses a weak pointer to the thread id internally. \begin{code} +threadIdPrimTy :: Type threadIdPrimTy = mkTyConTy threadIdPrimTyCon +threadIdPrimTyCon :: TyCon threadIdPrimTyCon = pcPrimTyCon0 threadIdPrimTyConName PtrRep \end{code}