%
% (c) The AQUA Project, Glasgow University, 1994-1998
%
\section[TysPrim]{Wired-in knowledge about primitive types}
\begin{code}
module TysPrim(
mkPrimTyConName,
tyVarList, alphaTyVars, betaTyVars, alphaTyVar, betaTyVar, gammaTyVar, deltaTyVar,
alphaTy, betaTy, gammaTy, deltaTy,
openAlphaTy, openBetaTy, openAlphaTyVar, openBetaTyVar, openAlphaTyVars,
kKiVar,
superKindTyCon, superKind, anyKindTyCon, liftedTypeKindTyCon,
openTypeKindTyCon, unliftedTypeKindTyCon, constraintKindTyCon,
superKindTyConName, anyKindTyConName, liftedTypeKindTyConName,
openTypeKindTyConName, unliftedTypeKindTyConName,
constraintKindTyConName,
anyKind, liftedTypeKind, unliftedTypeKind, openTypeKind, constraintKind,
mkArrowKind, mkArrowKinds,
funTyCon, funTyConName,
primTyCons,
charPrimTyCon, charPrimTy,
intPrimTyCon, intPrimTy,
wordPrimTyCon, wordPrimTy,
addrPrimTyCon, addrPrimTy,
floatPrimTyCon, floatPrimTy,
doublePrimTyCon, doublePrimTy,
voidPrimTyCon, voidPrimTy,
statePrimTyCon, mkStatePrimTy,
realWorldTyCon, realWorldTy, realWorldStatePrimTy,
proxyPrimTyCon, mkProxyPrimTy,
arrayPrimTyCon, mkArrayPrimTy,
byteArrayPrimTyCon, byteArrayPrimTy,
arrayArrayPrimTyCon, mkArrayArrayPrimTy,
mutableArrayPrimTyCon, mkMutableArrayPrimTy,
mutableByteArrayPrimTyCon, mkMutableByteArrayPrimTy,
mutableArrayArrayPrimTyCon, mkMutableArrayArrayPrimTy,
mutVarPrimTyCon, mkMutVarPrimTy,
mVarPrimTyCon, mkMVarPrimTy,
tVarPrimTyCon, mkTVarPrimTy,
stablePtrPrimTyCon, mkStablePtrPrimTy,
stableNamePrimTyCon, mkStableNamePrimTy,
bcoPrimTyCon, bcoPrimTy,
weakPrimTyCon, mkWeakPrimTy,
threadIdPrimTyCon, threadIdPrimTy,
int32PrimTyCon, int32PrimTy,
word32PrimTyCon, word32PrimTy,
int64PrimTyCon, int64PrimTy,
word64PrimTyCon, word64PrimTy,
eqPrimTyCon,
eqReprPrimTyCon,
anyTy, anyTyCon, anyTypeOfKind,
#include "primop-vector-tys-exports.hs-incl"
) where
#include "HsVersions.h"
import Var ( TyVar, KindVar, mkTyVar )
import Name ( Name, BuiltInSyntax(..), mkInternalName, mkWiredInName )
import OccName ( mkTyVarOccFS, mkTcOccFS )
import TyCon
import TypeRep
import SrcLoc
import Unique ( mkAlphaTyVarUnique )
import PrelNames
import FastString
import Data.Char
\end{code}
%************************************************************************
%* *
\subsection{Primitive type constructors}
%* *
%************************************************************************
\begin{code}
primTyCons :: [TyCon]
primTyCons
= [ addrPrimTyCon
, arrayPrimTyCon
, byteArrayPrimTyCon
, arrayArrayPrimTyCon
, charPrimTyCon
, doublePrimTyCon
, floatPrimTyCon
, intPrimTyCon
, int32PrimTyCon
, int64PrimTyCon
, bcoPrimTyCon
, weakPrimTyCon
, mutableArrayPrimTyCon
, mutableByteArrayPrimTyCon
, mutableArrayArrayPrimTyCon
, mVarPrimTyCon
, tVarPrimTyCon
, mutVarPrimTyCon
, realWorldTyCon
, stablePtrPrimTyCon
, stableNamePrimTyCon
, statePrimTyCon
, voidPrimTyCon
, proxyPrimTyCon
, threadIdPrimTyCon
, wordPrimTyCon
, word32PrimTyCon
, word64PrimTyCon
, anyTyCon
, eqPrimTyCon
, eqReprPrimTyCon
, liftedTypeKindTyCon
, unliftedTypeKindTyCon
, openTypeKindTyCon
, constraintKindTyCon
, superKindTyCon
, anyKindTyCon
#include "primop-vector-tycons.hs-incl"
]
mkPrimTc :: FastString -> Unique -> TyCon -> Name
mkPrimTc fs unique tycon
= mkWiredInName gHC_PRIM (mkTcOccFS fs)
unique
(ATyCon tycon)
UserSyntax
charPrimTyConName, intPrimTyConName, int32PrimTyConName, int64PrimTyConName, wordPrimTyConName, word32PrimTyConName, word64PrimTyConName, addrPrimTyConName, floatPrimTyConName, doublePrimTyConName, statePrimTyConName, proxyPrimTyConName, realWorldTyConName, arrayPrimTyConName, arrayArrayPrimTyConName, byteArrayPrimTyConName, mutableArrayPrimTyConName, mutableByteArrayPrimTyConName, mutableArrayArrayPrimTyConName, mutVarPrimTyConName, mVarPrimTyConName, tVarPrimTyConName, stablePtrPrimTyConName, stableNamePrimTyConName, bcoPrimTyConName, weakPrimTyConName, threadIdPrimTyConName, eqPrimTyConName, eqReprPrimTyConName, voidPrimTyConName :: Name
charPrimTyConName = mkPrimTc (fsLit "Char#") charPrimTyConKey charPrimTyCon
intPrimTyConName = mkPrimTc (fsLit "Int#") intPrimTyConKey intPrimTyCon
int32PrimTyConName = mkPrimTc (fsLit "Int32#") int32PrimTyConKey int32PrimTyCon
int64PrimTyConName = mkPrimTc (fsLit "Int64#") int64PrimTyConKey int64PrimTyCon
wordPrimTyConName = mkPrimTc (fsLit "Word#") wordPrimTyConKey wordPrimTyCon
word32PrimTyConName = mkPrimTc (fsLit "Word32#") word32PrimTyConKey word32PrimTyCon
word64PrimTyConName = mkPrimTc (fsLit "Word64#") word64PrimTyConKey word64PrimTyCon
addrPrimTyConName = mkPrimTc (fsLit "Addr#") addrPrimTyConKey addrPrimTyCon
floatPrimTyConName = mkPrimTc (fsLit "Float#") floatPrimTyConKey floatPrimTyCon
doublePrimTyConName = mkPrimTc (fsLit "Double#") doublePrimTyConKey doublePrimTyCon
statePrimTyConName = mkPrimTc (fsLit "State#") statePrimTyConKey statePrimTyCon
voidPrimTyConName = mkPrimTc (fsLit "Void#") voidPrimTyConKey voidPrimTyCon
proxyPrimTyConName = mkPrimTc (fsLit "Proxy#") proxyPrimTyConKey proxyPrimTyCon
eqPrimTyConName = mkPrimTc (fsLit "~#") eqPrimTyConKey eqPrimTyCon
eqReprPrimTyConName = mkPrimTc (fsLit "~R#") eqReprPrimTyConKey eqReprPrimTyCon
realWorldTyConName = mkPrimTc (fsLit "RealWorld") realWorldTyConKey realWorldTyCon
arrayPrimTyConName = mkPrimTc (fsLit "Array#") arrayPrimTyConKey arrayPrimTyCon
byteArrayPrimTyConName = mkPrimTc (fsLit "ByteArray#") byteArrayPrimTyConKey byteArrayPrimTyCon
arrayArrayPrimTyConName = mkPrimTc (fsLit "ArrayArray#") arrayArrayPrimTyConKey arrayArrayPrimTyCon
mutableArrayPrimTyConName = mkPrimTc (fsLit "MutableArray#") mutableArrayPrimTyConKey mutableArrayPrimTyCon
mutableByteArrayPrimTyConName = mkPrimTc (fsLit "MutableByteArray#") mutableByteArrayPrimTyConKey mutableByteArrayPrimTyCon
mutableArrayArrayPrimTyConName= mkPrimTc (fsLit "MutableArrayArray#") mutableArrayArrayPrimTyConKey mutableArrayArrayPrimTyCon
mutVarPrimTyConName = mkPrimTc (fsLit "MutVar#") mutVarPrimTyConKey mutVarPrimTyCon
mVarPrimTyConName = mkPrimTc (fsLit "MVar#") mVarPrimTyConKey mVarPrimTyCon
tVarPrimTyConName = mkPrimTc (fsLit "TVar#") tVarPrimTyConKey tVarPrimTyCon
stablePtrPrimTyConName = mkPrimTc (fsLit "StablePtr#") stablePtrPrimTyConKey stablePtrPrimTyCon
stableNamePrimTyConName = mkPrimTc (fsLit "StableName#") stableNamePrimTyConKey stableNamePrimTyCon
bcoPrimTyConName = mkPrimTc (fsLit "BCO#") bcoPrimTyConKey bcoPrimTyCon
weakPrimTyConName = mkPrimTc (fsLit "Weak#") weakPrimTyConKey weakPrimTyCon
threadIdPrimTyConName = mkPrimTc (fsLit "ThreadId#") threadIdPrimTyConKey threadIdPrimTyCon
\end{code}
%************************************************************************
%* *
\subsection{Support code}
%* *
%************************************************************************
alphaTyVars is a list of type variables for use in templates:
["a", "b", ..., "z", "t1", "t2", ... ]
\begin{code}
tyVarList :: Kind -> [TyVar]
tyVarList kind = [ mkTyVar (mkInternalName (mkAlphaTyVarUnique u)
(mkTyVarOccFS (mkFastString name))
noSrcSpan) kind
| u <- [2..],
let name | c <= 'z' = [c]
| otherwise = 't':show u
where c = chr (u2 + ord 'a')
]
alphaTyVars :: [TyVar]
alphaTyVars = tyVarList liftedTypeKind
betaTyVars :: [TyVar]
betaTyVars = tail alphaTyVars
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
openAlphaTyVars :: [TyVar]
openAlphaTyVar, openBetaTyVar :: TyVar
openAlphaTyVars@(openAlphaTyVar:openBetaTyVar:_) = tyVarList openTypeKind
openAlphaTy, openBetaTy :: Type
openAlphaTy = mkTyVarTy openAlphaTyVar
openBetaTy = mkTyVarTy openBetaTyVar
kKiVar :: KindVar
kKiVar = (tyVarList superKind) !! 10
\end{code}
%************************************************************************
%* *
FunTyCon
%* *
%************************************************************************
\begin{code}
funTyConName :: Name
funTyConName = mkPrimTyConName (fsLit "(->)") funTyConKey funTyCon
funTyCon :: TyCon
funTyCon = mkFunTyCon funTyConName $
mkArrowKinds [liftedTypeKind, liftedTypeKind] liftedTypeKind
\end{code}
%************************************************************************
%* *
Kinds
%* *
%************************************************************************
Note [SuperKind (BOX)]
~~~~~~~~~~~~~~~~~~~~~~
Kinds are classified by "super-kinds". There is only one super-kind, namely BOX.
Perhaps surprisingly we give BOX the kind BOX, thus BOX :: BOX
Reason: we want to have kind equalities, thus (without the kind applications)
keq :: * ~ * = Eq#
Remember that
(~) :: forall (k:BOX). k -> k -> Constraint
(~#) :: forall (k:BOX). k -> k -> #
Eq# :: forall (k:BOX). forall (a:k) (b:k). (~#) k a b -> (~) k a b
So the full defn of keq is
keq :: (~) BOX * * = Eq# BOX * *
So you can see it's convenient to have BOX:BOX
\begin{code}
superKindTyCon, anyKindTyCon, liftedTypeKindTyCon,
openTypeKindTyCon, unliftedTypeKindTyCon,
constraintKindTyCon
:: TyCon
superKindTyConName, anyKindTyConName, liftedTypeKindTyConName,
openTypeKindTyConName, unliftedTypeKindTyConName,
constraintKindTyConName
:: Name
superKindTyCon = mkKindTyCon superKindTyConName superKind
anyKindTyCon = mkKindTyCon anyKindTyConName superKind
liftedTypeKindTyCon = mkKindTyCon liftedTypeKindTyConName superKind
openTypeKindTyCon = mkKindTyCon openTypeKindTyConName superKind
unliftedTypeKindTyCon = mkKindTyCon unliftedTypeKindTyConName superKind
constraintKindTyCon = mkKindTyCon constraintKindTyConName superKind
superKindTyConName = mkPrimTyConName (fsLit "BOX") superKindTyConKey superKindTyCon
anyKindTyConName = mkPrimTyConName (fsLit "AnyK") anyKindTyConKey anyKindTyCon
liftedTypeKindTyConName = mkPrimTyConName (fsLit "*") liftedTypeKindTyConKey liftedTypeKindTyCon
openTypeKindTyConName = mkPrimTyConName (fsLit "OpenKind") openTypeKindTyConKey openTypeKindTyCon
unliftedTypeKindTyConName = mkPrimTyConName (fsLit "#") unliftedTypeKindTyConKey unliftedTypeKindTyCon
constraintKindTyConName = mkPrimTyConName (fsLit "Constraint") constraintKindTyConKey constraintKindTyCon
mkPrimTyConName :: FastString -> Unique -> TyCon -> Name
mkPrimTyConName occ key tycon = mkWiredInName gHC_PRIM (mkTcOccFS occ)
key
(ATyCon tycon)
BuiltInSyntax
\end{code}
\begin{code}
kindTyConType :: TyCon -> Type
kindTyConType kind = TyConApp kind []
anyKind, liftedTypeKind, unliftedTypeKind, openTypeKind, constraintKind, superKind :: Kind
superKind = kindTyConType superKindTyCon
anyKind = kindTyConType anyKindTyCon
liftedTypeKind = kindTyConType liftedTypeKindTyCon
unliftedTypeKind = kindTyConType unliftedTypeKindTyCon
openTypeKind = kindTyConType openTypeKindTyCon
constraintKind = kindTyConType constraintKindTyCon
mkArrowKind :: Kind -> Kind -> Kind
mkArrowKind k1 k2 = FunTy k1 k2
mkArrowKinds :: [Kind] -> Kind -> Kind
mkArrowKinds arg_kinds result_kind = foldr mkArrowKind result_kind arg_kinds
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-basic]{Basic primitive types (@Char#@, @Int#@, etc.)}
%* *
%************************************************************************
\begin{code}
pcPrimTyCon :: Name -> [Role] -> PrimRep -> TyCon
pcPrimTyCon name roles rep
= mkPrimTyCon name kind roles rep
where
kind = mkArrowKinds (map (const liftedTypeKind) roles) result_kind
result_kind = unliftedTypeKind
pcPrimTyCon0 :: Name -> PrimRep -> TyCon
pcPrimTyCon0 name rep
= mkPrimTyCon name result_kind [] 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}
%************************************************************************
%* *
\subsection[TysPrim-state]{The @State#@ type (and @_RealWorld@ types)}
%* *
%************************************************************************
Note [The ~# TyCon)
~~~~~~~~~~~~~~~~~~~~
There is a perfectly ordinary type constructor ~# that represents the type
of coercions (which, remember, are values). For example
Refl Int :: ~# * Int Int
It is a kind-polymorphic type constructor like Any:
Refl Maybe :: ~# (* -> *) Maybe Maybe
(~) only appears saturated. So we check that in CoreLint (and, in an
assertion, in Kind.typeKind).
Note [The State# TyCon]
~~~~~~~~~~~~~~~~~~~~~~~
State# is the primitive, unlifted type of states. It has one type parameter,
thus
State# RealWorld
or
State# s
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.
The type parameter to State# is intended to keep separate threads separate.
Even though this parameter is not used in the definition of State#, it is
given role Nominal to enforce its intended use.
\begin{code}
mkStatePrimTy :: Type -> Type
mkStatePrimTy ty = TyConApp statePrimTyCon [ty]
statePrimTyCon :: TyCon
statePrimTyCon = pcPrimTyCon statePrimTyConName [Nominal] VoidRep
voidPrimTy :: Type
voidPrimTy = TyConApp voidPrimTyCon []
voidPrimTyCon :: TyCon
voidPrimTyCon = pcPrimTyCon voidPrimTyConName [] VoidRep
mkProxyPrimTy :: Type -> Type -> Type
mkProxyPrimTy k ty = TyConApp proxyPrimTyCon [k, ty]
proxyPrimTyCon :: TyCon
proxyPrimTyCon = mkPrimTyCon proxyPrimTyConName kind [Nominal,Nominal] VoidRep
where kind = ForAllTy kv $ mkArrowKind k unliftedTypeKind
kv = kKiVar
k = mkTyVarTy kv
eqPrimTyCon :: TyCon
eqPrimTyCon = mkPrimTyCon eqPrimTyConName kind [Nominal, Nominal, Nominal] VoidRep
where kind = ForAllTy kv $ mkArrowKinds [k, k] unliftedTypeKind
kv = kKiVar
k = mkTyVarTy kv
eqReprPrimTyCon :: TyCon
eqReprPrimTyCon = mkPrimTyCon eqReprPrimTyConName kind
[Nominal, Representational, Representational] VoidRep
where kind = ForAllTy kv $ mkArrowKinds [k, k] unliftedTypeKind
kv = kKiVar
k = mkTyVarTy kv
\end{code}
RealWorld is deeply magical. It is *primitive*, but it is not
*unlifted* (hence ptrArg). We never manipulate values of type
RealWorld; it's only used in the type system, to parameterise State#.
\begin{code}
realWorldTyCon :: TyCon
realWorldTyCon = mkLiftedPrimTyCon realWorldTyConName liftedTypeKind [] PtrRep
realWorldTy :: Type
realWorldTy = mkTyConTy realWorldTyCon
realWorldStatePrimTy :: Type
realWorldStatePrimTy = mkStatePrimTy realWorldTy
\end{code}
Note: the ``state-pairing'' types are not truly primitive, so they are
defined in \tr{TysWiredIn.lhs}, not here.
%************************************************************************
%* *
\subsection[TysPrim-arrays]{The primitive array types}
%* *
%************************************************************************
\begin{code}
arrayPrimTyCon, mutableArrayPrimTyCon, mutableByteArrayPrimTyCon,
byteArrayPrimTyCon, arrayArrayPrimTyCon, mutableArrayArrayPrimTyCon :: TyCon
arrayPrimTyCon = pcPrimTyCon arrayPrimTyConName [Representational] PtrRep
mutableArrayPrimTyCon = pcPrimTyCon mutableArrayPrimTyConName [Nominal, Representational] PtrRep
mutableByteArrayPrimTyCon = pcPrimTyCon mutableByteArrayPrimTyConName [Nominal] PtrRep
byteArrayPrimTyCon = pcPrimTyCon0 byteArrayPrimTyConName PtrRep
arrayArrayPrimTyCon = pcPrimTyCon0 arrayArrayPrimTyConName PtrRep
mutableArrayArrayPrimTyCon = pcPrimTyCon mutableArrayArrayPrimTyConName [Nominal] PtrRep
mkArrayPrimTy :: Type -> Type
mkArrayPrimTy elt = TyConApp arrayPrimTyCon [elt]
byteArrayPrimTy :: Type
byteArrayPrimTy = mkTyConTy byteArrayPrimTyCon
mkArrayArrayPrimTy :: Type
mkArrayArrayPrimTy = mkTyConTy arrayArrayPrimTyCon
mkMutableArrayPrimTy :: Type -> Type -> Type
mkMutableArrayPrimTy s elt = TyConApp mutableArrayPrimTyCon [s, elt]
mkMutableByteArrayPrimTy :: Type -> Type
mkMutableByteArrayPrimTy s = TyConApp mutableByteArrayPrimTyCon [s]
mkMutableArrayArrayPrimTy :: Type -> Type
mkMutableArrayArrayPrimTy s = TyConApp mutableArrayArrayPrimTyCon [s]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-mut-var]{The mutable variable type}
%* *
%************************************************************************
\begin{code}
mutVarPrimTyCon :: TyCon
mutVarPrimTyCon = pcPrimTyCon mutVarPrimTyConName [Nominal, Representational] PtrRep
mkMutVarPrimTy :: Type -> Type -> Type
mkMutVarPrimTy s elt = TyConApp mutVarPrimTyCon [s, elt]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-synch-var]{The synchronizing variable type}
%* *
%************************************************************************
\begin{code}
mVarPrimTyCon :: TyCon
mVarPrimTyCon = pcPrimTyCon mVarPrimTyConName [Nominal, Representational] PtrRep
mkMVarPrimTy :: Type -> Type -> Type
mkMVarPrimTy s elt = TyConApp mVarPrimTyCon [s, elt]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-stm-var]{The transactional variable type}
%* *
%************************************************************************
\begin{code}
tVarPrimTyCon :: TyCon
tVarPrimTyCon = pcPrimTyCon tVarPrimTyConName [Nominal, Representational] PtrRep
mkTVarPrimTy :: Type -> Type -> Type
mkTVarPrimTy s elt = TyConApp tVarPrimTyCon [s, elt]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-stable-ptrs]{The stable-pointer type}
%* *
%************************************************************************
\begin{code}
stablePtrPrimTyCon :: TyCon
stablePtrPrimTyCon = pcPrimTyCon stablePtrPrimTyConName [Representational] AddrRep
mkStablePtrPrimTy :: Type -> Type
mkStablePtrPrimTy ty = TyConApp stablePtrPrimTyCon [ty]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-stable-names]{The stable-name type}
%* *
%************************************************************************
\begin{code}
stableNamePrimTyCon :: TyCon
stableNamePrimTyCon = pcPrimTyCon stableNamePrimTyConName [Representational] PtrRep
mkStableNamePrimTy :: Type -> Type
mkStableNamePrimTy ty = TyConApp stableNamePrimTyCon [ty]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-BCOs]{The ``bytecode object'' type}
%* *
%************************************************************************
\begin{code}
bcoPrimTy :: Type
bcoPrimTy = mkTyConTy bcoPrimTyCon
bcoPrimTyCon :: TyCon
bcoPrimTyCon = pcPrimTyCon0 bcoPrimTyConName PtrRep
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-Weak]{The ``weak pointer'' type}
%* *
%************************************************************************
\begin{code}
weakPrimTyCon :: TyCon
weakPrimTyCon = pcPrimTyCon weakPrimTyConName [Representational] PtrRep
mkWeakPrimTy :: Type -> Type
mkWeakPrimTy v = TyConApp weakPrimTyCon [v]
\end{code}
%************************************************************************
%* *
\subsection[TysPrim-thread-ids]{The ``thread id'' type}
%* *
%************************************************************************
A thread id is represented by a pointer to the TSO itself, to ensure
that they are always unique and we can always find the TSO for a given
thread id. However, this has the unfortunate consequence that a
ThreadId# for a given thread is treated as a root by the garbage
collector and can keep TSOs around for too long.
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}
%************************************************************************
%* *
Any
%* *
%************************************************************************
Note [Any types]
~~~~~~~~~~~~~~~~
The type constructor Any of kind forall k. k -> k 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
* It is a *closed* type family, with no instances. This means that
if ty :: '(k1, k2) we add a given coercion
g :: ty ~ (Fst ty, Snd ty)
If Any was a *data* type, then we'd get inconsistency because 'ty'
could be (Any '(k1,k2)) and then we'd have an equality with Any on
one side and '(,) on the other
* 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 Any, 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
For example length Any []
See Note [Strangely-kinded void TyCons]
Note [Any kinds]
~~~~~~~~~~~~~~~~
The type constructor AnyK (of sort BOX) is used internally only to zonk kind
variables with no constraints on them. It appears in similar circumstances to
Any, but at the kind level. For example:
type family Length (l :: [k]) :: Nat
type instance Length [] = Zero
Length is kind-polymorphic, and when applied to the empty (promoted) list it
will have the kind Length AnyK [].
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
anyTy :: Type
anyTy = mkTyConTy anyTyCon
anyTyCon :: TyCon
anyTyCon = mkLiftedPrimTyCon anyTyConName kind [Nominal] PtrRep
where kind = ForAllTy kKiVar (mkTyVarTy kKiVar)
anyTypeOfKind :: Kind -> Type
anyTypeOfKind kind = TyConApp anyTyCon [kind]
\end{code}
%************************************************************************
%* *
\subsection{SIMD vector types}
%* *
%************************************************************************
\begin{code}
#include "primop-vector-tys.hs-incl"
\end{code}