{-
(c) The AQUA Project, Glasgow University, 1994-1998


Wired-in knowledge about primitive types
-}

{-# LANGUAGE CPP #-}
{-# OPTIONS_GHC -Wno-incomplete-uni-patterns #-}

-- | This module defines TyCons that can't be expressed in Haskell.
--   They are all, therefore, wired-in TyCons.  C.f module "GHC.Builtin.Types"
module GHC.Builtin.Types.Prim(
        mkTemplateKindVar, mkTemplateKindVars,
        mkTemplateTyVars, mkTemplateTyVarsFrom,
        mkTemplateKiTyVars, mkTemplateKiTyVar,

        mkTemplateTyConBinders, mkTemplateKindTyConBinders,
        mkTemplateAnonTyConBinders,

        alphaTyVars, alphaTyVar, betaTyVar, gammaTyVar, deltaTyVar,
        alphaTyVarSpec, betaTyVarSpec, gammaTyVarSpec, deltaTyVarSpec,
        alphaTys, alphaTy, betaTy, gammaTy, deltaTy,
        alphaTyVarsUnliftedRep, alphaTyVarUnliftedRep,
        alphaTysUnliftedRep, alphaTyUnliftedRep,
        runtimeRep1TyVar, runtimeRep2TyVar, runtimeRep3TyVar,
        runtimeRep1TyVarInf, runtimeRep2TyVarInf,
        runtimeRep1Ty, runtimeRep2Ty, runtimeRep3Ty,
        levity1TyVar, levity2TyVar,
        levity1TyVarInf, levity2TyVarInf,
        levity1Ty, levity2Ty,

        alphaConstraintTyVar, alphaConstraintTy,

        openAlphaTyVar, openBetaTyVar, openGammaTyVar,
        openAlphaTyVarSpec, openBetaTyVarSpec, openGammaTyVarSpec,
        openAlphaTy, openBetaTy, openGammaTy,

        levPolyAlphaTyVar, levPolyBetaTyVar,
        levPolyAlphaTyVarSpec, levPolyBetaTyVarSpec,
        levPolyAlphaTy, levPolyBetaTy,

        multiplicityTyVar1, multiplicityTyVar2,

        -- Kind constructors...
        tYPETyCon, tYPETyConName, tYPEKind,
        cONSTRAINTTyCon, cONSTRAINTTyConName, cONSTRAINTKind,

        -- Arrows
        funTyFlagTyCon, isArrowTyCon,
        fUNTyCon,       fUNTyConName,
        ctArrowTyCon, ctArrowTyConName,
        ccArrowTyCon, ccArrowTyConName,
        tcArrowTyCon, tcArrowTyConName,

        unexposedPrimTyCons, exposedPrimTyCons, primTyCons,

        charPrimTyCon,          charPrimTy, charPrimTyConName,
        intPrimTyCon,           intPrimTy, intPrimTyConName,
        wordPrimTyCon,          wordPrimTy, wordPrimTyConName,
        addrPrimTyCon,          addrPrimTy, addrPrimTyConName,
        floatPrimTyCon,         floatPrimTy, floatPrimTyConName,
        doublePrimTyCon,        doublePrimTy, doublePrimTyConName,

        statePrimTyCon,         mkStatePrimTy,
        realWorldTyCon,         realWorldTy, realWorldStatePrimTy,

        proxyPrimTyCon,         mkProxyPrimTy,

        arrayPrimTyCon, mkArrayPrimTy,
        byteArrayPrimTyCon,     byteArrayPrimTy,
        smallArrayPrimTyCon, mkSmallArrayPrimTy,
        mutableArrayPrimTyCon, mkMutableArrayPrimTy,
        mutableByteArrayPrimTyCon, mkMutableByteArrayPrimTy,
        smallMutableArrayPrimTyCon, mkSmallMutableArrayPrimTy,
        mutVarPrimTyCon, mkMutVarPrimTy,

        mVarPrimTyCon,                  mkMVarPrimTy,
        ioPortPrimTyCon,                mkIOPortPrimTy,
        tVarPrimTyCon,                  mkTVarPrimTy,
        stablePtrPrimTyCon,             mkStablePtrPrimTy,
        stableNamePrimTyCon,            mkStableNamePrimTy,
        compactPrimTyCon,               compactPrimTy,
        bcoPrimTyCon,                   bcoPrimTy,
        weakPrimTyCon,                  mkWeakPrimTy,
        threadIdPrimTyCon,              threadIdPrimTy,
        stackSnapshotPrimTyCon,         stackSnapshotPrimTy,
        promptTagPrimTyCon,             mkPromptTagPrimTy,

        int8PrimTyCon,          int8PrimTy, int8PrimTyConName,
        word8PrimTyCon,         word8PrimTy, word8PrimTyConName,

        int16PrimTyCon,         int16PrimTy, int16PrimTyConName,
        word16PrimTyCon,        word16PrimTy, word16PrimTyConName,

        int32PrimTyCon,         int32PrimTy, int32PrimTyConName,
        word32PrimTyCon,        word32PrimTy, word32PrimTyConName,

        int64PrimTyCon,         int64PrimTy, int64PrimTyConName,
        word64PrimTyCon,        word64PrimTy, word64PrimTyConName,

        eqPrimTyCon,            -- ty1 ~# ty2
        eqReprPrimTyCon,        -- ty1 ~R# ty2  (at role Representational)
        eqPhantPrimTyCon,       -- ty1 ~P# ty2  (at role Phantom)
        equalityTyCon,

        -- * SIMD
#include "primop-vector-tys-exports.hs-incl"
  ) where

import GHC.Prelude

import {-# SOURCE #-} GHC.Builtin.Types
  ( runtimeRepTy, levityTy, unboxedTupleKind, liftedTypeKind, unliftedTypeKind
  , boxedRepDataConTyCon, vecRepDataConTyCon
  , liftedRepTy, unliftedRepTy, zeroBitRepTy
  , intRepDataConTy
  , int8RepDataConTy, int16RepDataConTy, int32RepDataConTy, int64RepDataConTy
  , wordRepDataConTy
  , word16RepDataConTy, word8RepDataConTy, word32RepDataConTy, word64RepDataConTy
  , addrRepDataConTy
  , floatRepDataConTy, doubleRepDataConTy
  , vec2DataConTy, vec4DataConTy, vec8DataConTy, vec16DataConTy, vec32DataConTy
  , vec64DataConTy
  , int8ElemRepDataConTy, int16ElemRepDataConTy, int32ElemRepDataConTy
  , int64ElemRepDataConTy, word8ElemRepDataConTy, word16ElemRepDataConTy
  , word32ElemRepDataConTy, word64ElemRepDataConTy, floatElemRepDataConTy
  , doubleElemRepDataConTy
  , multiplicityTy
  , constraintKind )

import {-# SOURCE #-} GHC.Types.TyThing( mkATyCon )
import {-# SOURCE #-} GHC.Core.Type ( mkTyConApp, getLevity )

import GHC.Core.TyCon
import GHC.Core.TyCo.Rep -- Doesn't need special access, but this is easier to avoid
                         -- import loops which show up if you import Type instead

import GHC.Types.Var    ( TyVarBinder, TyVar,binderVar, binderVars
                        , mkTyVar, mkTyVarBinder, mkTyVarBinders )
import GHC.Types.Name
import GHC.Types.SrcLoc
import GHC.Types.Unique

import GHC.Builtin.Uniques
import GHC.Builtin.Names
import GHC.Utils.Misc ( changeLast )
import GHC.Utils.Panic ( assertPpr )
import GHC.Utils.Outputable

import GHC.Data.FastString
import Data.Char

{- *********************************************************************
*                                                                      *
             Building blocks
*                                                                      *
********************************************************************* -}

mk_TYPE_app :: Type -> Type
mk_TYPE_app :: Type -> Type
mk_TYPE_app Type
rep = TyCon -> [Type] -> Type
mkTyConApp TyCon
tYPETyCon [Type
rep]

mk_CONSTRAINT_app :: Type -> Type
mk_CONSTRAINT_app :: Type -> Type
mk_CONSTRAINT_app Type
rep = TyCon -> [Type] -> Type
mkTyConApp TyCon
cONSTRAINTTyCon [Type
rep]

mkPrimTc :: FastString -> Unique -> TyCon -> Name
mkPrimTc :: FastString -> Unique -> TyCon -> Name
mkPrimTc = BuiltInSyntax -> FastString -> Unique -> TyCon -> Name
mkGenPrimTc BuiltInSyntax
UserSyntax

mkBuiltInPrimTc :: FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc :: FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc = BuiltInSyntax -> FastString -> Unique -> TyCon -> Name
mkGenPrimTc BuiltInSyntax
BuiltInSyntax

mkGenPrimTc :: BuiltInSyntax -> FastString -> Unique -> TyCon -> Name
mkGenPrimTc :: BuiltInSyntax -> FastString -> Unique -> TyCon -> Name
mkGenPrimTc BuiltInSyntax
built_in_syntax FastString
occ Unique
key TyCon
tycon
  = Module -> OccName -> Unique -> TyThing -> BuiltInSyntax -> Name
mkWiredInName Module
gHC_PRIM (FastString -> OccName
mkTcOccFS FastString
occ)
                  Unique
key
                  (TyCon -> TyThing
mkATyCon TyCon
tycon)
                  BuiltInSyntax
built_in_syntax

-- | Create a primitive 'TyCon' with the given 'Name',
-- arguments of kind 'Type` with the given 'Role's,
-- and the given result kind representation.
--
-- Only use this in "GHC.Builtin.Types.Prim".
pcPrimTyCon :: Name
            -> [Role] -> RuntimeRepType -> TyCon
pcPrimTyCon :: Name -> [Role] -> Type -> TyCon
pcPrimTyCon Name
name [Role]
roles Type
res_rep
  = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
name [TyConBinder]
binders Type
result_kind [Role]
roles
  where
    bndr_kis :: [Type]
bndr_kis    = Type
liftedTypeKind forall (f :: * -> *) a b. Functor f => a -> f b -> f a
<$ [Role]
roles
    binders :: [TyConBinder]
binders     = [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [Type]
bndr_kis
    result_kind :: Type
result_kind = Type -> Type
mk_TYPE_app Type
res_rep

-- | Create a primitive nullary 'TyCon' with the given 'Name'
-- and result kind representation.
--
-- Only use this in "GHC.Builtin.Types.Prim".
pcPrimTyCon0 :: Name -> RuntimeRepType -> TyCon
pcPrimTyCon0 :: Name -> Type -> TyCon
pcPrimTyCon0 Name
name Type
res_rep
  = Name -> [Role] -> Type -> TyCon
pcPrimTyCon Name
name [] Type
res_rep

-- | Create a primitive 'TyCon' like 'pcPrimTyCon', except the last
-- argument is levity-polymorphic, where the levity argument is
-- implicit and comes before other arguments
--
-- Only use this in "GHC.Builtin.Types.Prim".
pcPrimTyCon_LevPolyLastArg :: Name
                           -> [Role] -- ^ roles of the arguments (must be non-empty),
                                     -- not including the implicit argument of kind 'Levity',
                                     -- which always has 'Nominal' role
                           -> RuntimeRepType  -- ^ representation of the fully-applied type
                           -> TyCon
pcPrimTyCon_LevPolyLastArg :: Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
name [Role]
roles Type
res_rep
  = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
name [TyConBinder]
binders Type
result_kind (Role
Nominal forall a. a -> [a] -> [a]
: [Role]
roles)
    where
      result_kind :: Type
result_kind = Type -> Type
mk_TYPE_app Type
res_rep
      lev_bndr :: TyConBinder
lev_bndr = ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
levity1TyVar
      binders :: [TyConBinder]
binders  = TyConBinder
lev_bndr forall a. a -> [a] -> [a]
: [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [Type]
anon_bndr_kis
      lev_tv :: Type
lev_tv   = TyVar -> Type
mkTyVarTy (forall tv argf. VarBndr tv argf -> tv
binderVar TyConBinder
lev_bndr)

      -- [ Type, ..., Type, TYPE (BoxedRep l) ]
      anon_bndr_kis :: [Type]
anon_bndr_kis = forall a. [a] -> a -> [a]
changeLast (Type
liftedTypeKind forall (f :: * -> *) a b. Functor f => a -> f b -> f a
<$ [Role]
roles) forall a b. (a -> b) -> a -> b
$
                      Type -> Type
mk_TYPE_app forall a b. (a -> b) -> a -> b
$
                      TyCon -> [Type] -> Type
mkTyConApp TyCon
boxedRepDataConTyCon [Type
lev_tv]


{- *********************************************************************
*                                                                      *
           Primitive type constructors
*                                                                      *
********************************************************************* -}

{- Note Note [Unexposed TyCons]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
A few primitive TyCons are "unexposed", meaning:
* We don't want users to be able to write them (see #15209);
  i.e. they aren't in scope, ever.  In particular they do not
  appear in the exports of GHC.Prim: see GHC.Builtin.Utils.ghcPrimExports

* We don't want users to see them in GHCi's @:browse@ output (see #12023).
-}

primTyCons :: [TyCon]
primTyCons :: [TyCon]
primTyCons = [TyCon]
unexposedPrimTyCons forall a. [a] -> [a] -> [a]
++ [TyCon]
exposedPrimTyCons

-- | Primitive 'TyCon's that are defined in GHC.Prim but not "exposed".
-- See Note [Unexposed TyCons]
unexposedPrimTyCons :: [TyCon]
unexposedPrimTyCons :: [TyCon]
unexposedPrimTyCons
  = [ TyCon
eqPrimTyCon      -- (~#)
    , TyCon
eqReprPrimTyCon  -- (~R#)
    , TyCon
eqPhantPrimTyCon -- (~P#)

    -- These arrows are un-exposed for now
    , TyCon
ctArrowTyCon  -- (=>)
    , TyCon
ccArrowTyCon  -- (==>)
    , TyCon
tcArrowTyCon  -- (-=>)
    ]

-- | Primitive 'TyCon's that are defined in, and exported from, GHC.Prim.
exposedPrimTyCons :: [TyCon]
exposedPrimTyCons :: [TyCon]
exposedPrimTyCons
  = [ TyCon
addrPrimTyCon
    , TyCon
arrayPrimTyCon
    , TyCon
byteArrayPrimTyCon
    , TyCon
smallArrayPrimTyCon
    , TyCon
charPrimTyCon
    , TyCon
doublePrimTyCon
    , TyCon
floatPrimTyCon
    , TyCon
intPrimTyCon
    , TyCon
int8PrimTyCon
    , TyCon
int16PrimTyCon
    , TyCon
int32PrimTyCon
    , TyCon
int64PrimTyCon
    , TyCon
bcoPrimTyCon
    , TyCon
weakPrimTyCon
    , TyCon
mutableArrayPrimTyCon
    , TyCon
mutableByteArrayPrimTyCon
    , TyCon
smallMutableArrayPrimTyCon
    , TyCon
mVarPrimTyCon
    , TyCon
ioPortPrimTyCon
    , TyCon
tVarPrimTyCon
    , TyCon
mutVarPrimTyCon
    , TyCon
realWorldTyCon
    , TyCon
stablePtrPrimTyCon
    , TyCon
stableNamePrimTyCon
    , TyCon
compactPrimTyCon
    , TyCon
statePrimTyCon
    , TyCon
proxyPrimTyCon
    , TyCon
threadIdPrimTyCon
    , TyCon
wordPrimTyCon
    , TyCon
word8PrimTyCon
    , TyCon
word16PrimTyCon
    , TyCon
word32PrimTyCon
    , TyCon
word64PrimTyCon
    , TyCon
stackSnapshotPrimTyCon
    , TyCon
promptTagPrimTyCon

    , TyCon
fUNTyCon
    , TyCon
tYPETyCon
    , TyCon
cONSTRAINTTyCon

#include "primop-vector-tycons.hs-incl"
    ]

charPrimTyConName, intPrimTyConName, int8PrimTyConName, int16PrimTyConName, int32PrimTyConName, int64PrimTyConName,
  wordPrimTyConName, word32PrimTyConName, word8PrimTyConName, word16PrimTyConName, word64PrimTyConName,
  addrPrimTyConName, floatPrimTyConName, doublePrimTyConName,
  statePrimTyConName, proxyPrimTyConName, realWorldTyConName,
  arrayPrimTyConName, smallArrayPrimTyConName, byteArrayPrimTyConName,
  mutableArrayPrimTyConName, mutableByteArrayPrimTyConName,
  smallMutableArrayPrimTyConName, mutVarPrimTyConName, mVarPrimTyConName,
  ioPortPrimTyConName, tVarPrimTyConName, stablePtrPrimTyConName,
  stableNamePrimTyConName, compactPrimTyConName, bcoPrimTyConName,
  weakPrimTyConName, threadIdPrimTyConName,
  eqPrimTyConName, eqReprPrimTyConName, eqPhantPrimTyConName,
  stackSnapshotPrimTyConName, promptTagPrimTyConName :: Name
charPrimTyConName :: Name
charPrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Char#") Unique
charPrimTyConKey TyCon
charPrimTyCon
intPrimTyConName :: Name
intPrimTyConName              = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Int#") Unique
intPrimTyConKey  TyCon
intPrimTyCon
int8PrimTyConName :: Name
int8PrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Int8#") Unique
int8PrimTyConKey TyCon
int8PrimTyCon
int16PrimTyConName :: Name
int16PrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Int16#") Unique
int16PrimTyConKey TyCon
int16PrimTyCon
int32PrimTyConName :: Name
int32PrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Int32#") Unique
int32PrimTyConKey TyCon
int32PrimTyCon
int64PrimTyConName :: Name
int64PrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Int64#") Unique
int64PrimTyConKey TyCon
int64PrimTyCon
wordPrimTyConName :: Name
wordPrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Word#") Unique
wordPrimTyConKey TyCon
wordPrimTyCon
word8PrimTyConName :: Name
word8PrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Word8#") Unique
word8PrimTyConKey TyCon
word8PrimTyCon
word16PrimTyConName :: Name
word16PrimTyConName           = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Word16#") Unique
word16PrimTyConKey TyCon
word16PrimTyCon
word32PrimTyConName :: Name
word32PrimTyConName           = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Word32#") Unique
word32PrimTyConKey TyCon
word32PrimTyCon
word64PrimTyConName :: Name
word64PrimTyConName           = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Word64#") Unique
word64PrimTyConKey TyCon
word64PrimTyCon
addrPrimTyConName :: Name
addrPrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Addr#") Unique
addrPrimTyConKey TyCon
addrPrimTyCon
floatPrimTyConName :: Name
floatPrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Float#") Unique
floatPrimTyConKey TyCon
floatPrimTyCon
doublePrimTyConName :: Name
doublePrimTyConName           = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Double#") Unique
doublePrimTyConKey TyCon
doublePrimTyCon
statePrimTyConName :: Name
statePrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"State#") Unique
statePrimTyConKey TyCon
statePrimTyCon
proxyPrimTyConName :: Name
proxyPrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Proxy#") Unique
proxyPrimTyConKey TyCon
proxyPrimTyCon
eqPrimTyConName :: Name
eqPrimTyConName               = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"~#") Unique
eqPrimTyConKey TyCon
eqPrimTyCon
eqReprPrimTyConName :: Name
eqReprPrimTyConName           = FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc (String -> FastString
fsLit String
"~R#") Unique
eqReprPrimTyConKey TyCon
eqReprPrimTyCon
eqPhantPrimTyConName :: Name
eqPhantPrimTyConName          = FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc (String -> FastString
fsLit String
"~P#") Unique
eqPhantPrimTyConKey TyCon
eqPhantPrimTyCon
realWorldTyConName :: Name
realWorldTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"RealWorld") Unique
realWorldTyConKey TyCon
realWorldTyCon
arrayPrimTyConName :: Name
arrayPrimTyConName            = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Array#") Unique
arrayPrimTyConKey TyCon
arrayPrimTyCon
byteArrayPrimTyConName :: Name
byteArrayPrimTyConName        = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"ByteArray#") Unique
byteArrayPrimTyConKey TyCon
byteArrayPrimTyCon
smallArrayPrimTyConName :: Name
smallArrayPrimTyConName       = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"SmallArray#") Unique
smallArrayPrimTyConKey TyCon
smallArrayPrimTyCon
mutableArrayPrimTyConName :: Name
mutableArrayPrimTyConName     = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"MutableArray#") Unique
mutableArrayPrimTyConKey TyCon
mutableArrayPrimTyCon
mutableByteArrayPrimTyConName :: Name
mutableByteArrayPrimTyConName = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"MutableByteArray#") Unique
mutableByteArrayPrimTyConKey TyCon
mutableByteArrayPrimTyCon
smallMutableArrayPrimTyConName :: Name
smallMutableArrayPrimTyConName= FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"SmallMutableArray#") Unique
smallMutableArrayPrimTyConKey TyCon
smallMutableArrayPrimTyCon
mutVarPrimTyConName :: Name
mutVarPrimTyConName           = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"MutVar#") Unique
mutVarPrimTyConKey TyCon
mutVarPrimTyCon
ioPortPrimTyConName :: Name
ioPortPrimTyConName           = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"IOPort#") Unique
ioPortPrimTyConKey TyCon
ioPortPrimTyCon
mVarPrimTyConName :: Name
mVarPrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"MVar#") Unique
mVarPrimTyConKey TyCon
mVarPrimTyCon
tVarPrimTyConName :: Name
tVarPrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"TVar#") Unique
tVarPrimTyConKey TyCon
tVarPrimTyCon
stablePtrPrimTyConName :: Name
stablePtrPrimTyConName        = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"StablePtr#") Unique
stablePtrPrimTyConKey TyCon
stablePtrPrimTyCon
stableNamePrimTyConName :: Name
stableNamePrimTyConName       = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"StableName#") Unique
stableNamePrimTyConKey TyCon
stableNamePrimTyCon
compactPrimTyConName :: Name
compactPrimTyConName          = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Compact#") Unique
compactPrimTyConKey TyCon
compactPrimTyCon
stackSnapshotPrimTyConName :: Name
stackSnapshotPrimTyConName    = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"StackSnapshot#") Unique
stackSnapshotPrimTyConKey TyCon
stackSnapshotPrimTyCon

#if MIN_VERSION_ghc_prim(0, 7, 0)
bcoPrimTyConName :: Name
bcoPrimTyConName              = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"BCO") Unique
bcoPrimTyConKey TyCon
bcoPrimTyCon
#else
bcoPrimTyConName              = mkPrimTc (fsLit "BCO#") bcoPrimTyConKey bcoPrimTyCon
#endif

weakPrimTyConName :: Name
weakPrimTyConName             = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"Weak#") Unique
weakPrimTyConKey TyCon
weakPrimTyCon
threadIdPrimTyConName :: Name
threadIdPrimTyConName         = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"ThreadId#") Unique
threadIdPrimTyConKey TyCon
threadIdPrimTyCon
promptTagPrimTyConName :: Name
promptTagPrimTyConName        = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"PromptTag#") Unique
promptTagPrimTyConKey TyCon
promptTagPrimTyCon

{- *********************************************************************
*                                                                      *
                Type variables
*                                                                      *
********************************************************************* -}

{-
alphaTyVars is a list of type variables for use in templates:
        ["a", "b", ..., "z", "t1", "t2", ... ]
-}

mkTemplateKindVar :: Kind -> TyVar
mkTemplateKindVar :: Type -> TyVar
mkTemplateKindVar = Name -> Type -> TyVar
mkTyVar (Int -> String -> Name
mk_tv_name Int
0 String
"k")

mkTemplateKindVars :: [Kind] -> [TyVar]
-- k0  with unique (mkAlphaTyVarUnique 0)
-- k1  with unique (mkAlphaTyVarUnique 1)
-- ... etc
mkTemplateKindVars :: [Type] -> [TyVar]
mkTemplateKindVars [Type
kind] = [Type -> TyVar
mkTemplateKindVar Type
kind]
  -- Special case for one kind: just "k"
mkTemplateKindVars [Type]
kinds
  = [ Name -> Type -> TyVar
mkTyVar (Int -> String -> Name
mk_tv_name Int
u (Char
'k' forall a. a -> [a] -> [a]
: forall a. Show a => a -> String
show Int
u)) Type
kind
    | (Type
kind, Int
u) <- [Type]
kinds forall a b. [a] -> [b] -> [(a, b)]
`zip` [Int
0..] ]
mk_tv_name :: Int -> String -> Name
mk_tv_name :: Int -> String -> Name
mk_tv_name Int
u String
s = Unique -> OccName -> SrcSpan -> Name
mkInternalName (Int -> Unique
mkAlphaTyVarUnique Int
u)
                                (FastString -> OccName
mkTyVarOccFS (String -> FastString
mkFastString String
s))
                                SrcSpan
noSrcSpan

mkTemplateTyVarsFrom :: Int -> [Kind] -> [TyVar]
-- a  with unique (mkAlphaTyVarUnique n)
-- b  with unique (mkAlphaTyVarUnique n+1)
-- ... etc
-- Typically called as
--   mkTemplateTyVarsFrom (length kv_bndrs) kinds
-- where kv_bndrs are the kind-level binders of a TyCon
mkTemplateTyVarsFrom :: Int -> [Type] -> [TyVar]
mkTemplateTyVarsFrom Int
n [Type]
kinds
  = [ Name -> Type -> TyVar
mkTyVar Name
name Type
kind
    | (Type
kind, Int
index) <- forall a b. [a] -> [b] -> [(a, b)]
zip [Type]
kinds [Int
0..],
      let ch_ord :: Int
ch_ord = Int
index forall a. Num a => a -> a -> a
+ Char -> Int
ord Char
'a'
          name_str :: String
name_str | Int
ch_ord forall a. Ord a => a -> a -> Bool
<= Char -> Int
ord Char
'z' = [Int -> Char
chr Int
ch_ord]
                   | Bool
otherwise         = Char
't'forall a. a -> [a] -> [a]
:forall a. Show a => a -> String
show Int
index
          name :: Name
name = Int -> String -> Name
mk_tv_name (Int
index forall a. Num a => a -> a -> a
+ Int
n) String
name_str
    ]

mkTemplateTyVars :: [Kind] -> [TyVar]
mkTemplateTyVars :: [Type] -> [TyVar]
mkTemplateTyVars = Int -> [Type] -> [TyVar]
mkTemplateTyVarsFrom Int
1

mkTemplateTyConBinders
    :: [Kind]                -- [k1, .., kn]   Kinds of kind-forall'd vars
    -> ([Kind] -> [Kind])    -- Arg is [kv1:k1, ..., kvn:kn]
                             --     same length as first arg
                             -- Result is anon arg kinds
    -> [TyConBinder]
mkTemplateTyConBinders :: [Type] -> ([Type] -> [Type]) -> [TyConBinder]
mkTemplateTyConBinders [Type]
kind_var_kinds [Type] -> [Type]
mk_anon_arg_kinds
  = [TyConBinder]
kv_bndrs forall a. [a] -> [a] -> [a]
++ [TyConBinder]
tv_bndrs
  where
    kv_bndrs :: [TyConBinder]
kv_bndrs   = [Type] -> [TyConBinder]
mkTemplateKindTyConBinders [Type]
kind_var_kinds
    anon_kinds :: [Type]
anon_kinds = [Type] -> [Type]
mk_anon_arg_kinds ([TyVar] -> [Type]
mkTyVarTys (forall tv argf. [VarBndr tv argf] -> [tv]
binderVars [TyConBinder]
kv_bndrs))
    tv_bndrs :: [TyConBinder]
tv_bndrs   = Int -> [Type] -> [TyConBinder]
mkTemplateAnonTyConBindersFrom (forall (t :: * -> *) a. Foldable t => t a -> Int
length [TyConBinder]
kv_bndrs) [Type]
anon_kinds

mkTemplateKiTyVars
    :: [Kind]                -- [k1, .., kn]   Kinds of kind-forall'd vars
    -> ([Kind] -> [Kind])    -- Arg is [kv1:k1, ..., kvn:kn]
                             --     same length as first arg
                             -- Result is anon arg kinds [ak1, .., akm]
    -> [TyVar]   -- [kv1:k1, ..., kvn:kn, av1:ak1, ..., avm:akm]
-- Example: if you want the tyvars for
--   forall (r:RuntimeRep) (a:TYPE r) (b:*). blah
-- call mkTemplateKiTyVars [RuntimeRep] (\[r] -> [TYPE r, *])
mkTemplateKiTyVars :: [Type] -> ([Type] -> [Type]) -> [TyVar]
mkTemplateKiTyVars [Type]
kind_var_kinds [Type] -> [Type]
mk_arg_kinds
  = [TyVar]
kv_bndrs forall a. [a] -> [a] -> [a]
++ [TyVar]
tv_bndrs
  where
    kv_bndrs :: [TyVar]
kv_bndrs   = [Type] -> [TyVar]
mkTemplateKindVars [Type]
kind_var_kinds
    anon_kinds :: [Type]
anon_kinds = [Type] -> [Type]
mk_arg_kinds ([TyVar] -> [Type]
mkTyVarTys [TyVar]
kv_bndrs)
    tv_bndrs :: [TyVar]
tv_bndrs   = Int -> [Type] -> [TyVar]
mkTemplateTyVarsFrom (forall (t :: * -> *) a. Foldable t => t a -> Int
length [TyVar]
kv_bndrs) [Type]
anon_kinds

mkTemplateKiTyVar
    :: Kind                  -- [k1, .., kn]   Kind of kind-forall'd var
    -> (Kind -> [Kind])      -- Arg is kv1:k1
                             -- Result is anon arg kinds [ak1, .., akm]
    -> [TyVar]   -- [kv1:k1, ..., kvn:kn, av1:ak1, ..., avm:akm]
-- Example: if you want the tyvars for
--   forall (r:RuntimeRep) (a:TYPE r) (b:*). blah
-- call mkTemplateKiTyVar RuntimeRep (\r -> [TYPE r, *])
mkTemplateKiTyVar :: Type -> (Type -> [Type]) -> [TyVar]
mkTemplateKiTyVar Type
kind Type -> [Type]
mk_arg_kinds
  = TyVar
kv_bndr forall a. a -> [a] -> [a]
: [TyVar]
tv_bndrs
  where
    kv_bndr :: TyVar
kv_bndr    = Type -> TyVar
mkTemplateKindVar Type
kind
    anon_kinds :: [Type]
anon_kinds = Type -> [Type]
mk_arg_kinds (TyVar -> Type
mkTyVarTy TyVar
kv_bndr)
    tv_bndrs :: [TyVar]
tv_bndrs   = Int -> [Type] -> [TyVar]
mkTemplateTyVarsFrom Int
1 [Type]
anon_kinds

mkTemplateKindTyConBinders :: [Kind] -> [TyConBinder]
-- Makes named, Specified binders
mkTemplateKindTyConBinders :: [Type] -> [TyConBinder]
mkTemplateKindTyConBinders [Type]
kinds
  = [ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Specified TyVar
tv | TyVar
tv <- [Type] -> [TyVar]
mkTemplateKindVars [Type]
kinds]

mkTemplateAnonTyConBinders :: [Kind] -> [TyConBinder]
mkTemplateAnonTyConBinders :: [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [Type]
kinds
  = [TyVar] -> [TyConBinder]
mkAnonTyConBinders ([Type] -> [TyVar]
mkTemplateTyVars [Type]
kinds)

mkTemplateAnonTyConBindersFrom :: Int -> [Kind] -> [TyConBinder]
mkTemplateAnonTyConBindersFrom :: Int -> [Type] -> [TyConBinder]
mkTemplateAnonTyConBindersFrom Int
n [Type]
kinds
  = [TyVar] -> [TyConBinder]
mkAnonTyConBinders (Int -> [Type] -> [TyVar]
mkTemplateTyVarsFrom Int
n [Type]
kinds)

alphaTyVars :: [TyVar]
alphaTyVars :: [TyVar]
alphaTyVars = [Type] -> [TyVar]
mkTemplateTyVars forall a b. (a -> b) -> a -> b
$ forall a. a -> [a]
repeat Type
liftedTypeKind

alphaTyVar, betaTyVar, gammaTyVar, deltaTyVar :: TyVar
(TyVar
alphaTyVar:TyVar
betaTyVar:TyVar
gammaTyVar:TyVar
deltaTyVar:[TyVar]
_) = [TyVar]
alphaTyVars

alphaTyVarSpec, betaTyVarSpec, gammaTyVarSpec, deltaTyVarSpec :: TyVarBinder
(TyVarBinder
alphaTyVarSpec:TyVarBinder
betaTyVarSpec:TyVarBinder
gammaTyVarSpec:TyVarBinder
deltaTyVarSpec:[TyVarBinder]
_) = forall vis. vis -> [TyVar] -> [VarBndr TyVar vis]
mkTyVarBinders ForAllTyFlag
Specified [TyVar]
alphaTyVars

alphaConstraintTyVars :: [TyVar]
alphaConstraintTyVars :: [TyVar]
alphaConstraintTyVars = [Type] -> [TyVar]
mkTemplateTyVars forall a b. (a -> b) -> a -> b
$ forall a. a -> [a]
repeat Type
constraintKind

alphaConstraintTyVar :: TyVar
(TyVar
alphaConstraintTyVar:[TyVar]
_) = [TyVar]
alphaConstraintTyVars

alphaConstraintTy :: Type
alphaConstraintTy :: Type
alphaConstraintTy = TyVar -> Type
mkTyVarTy TyVar
alphaConstraintTyVar

alphaTys :: [Type]
alphaTys :: [Type]
alphaTys = [TyVar] -> [Type]
mkTyVarTys [TyVar]
alphaTyVars
alphaTy, betaTy, gammaTy, deltaTy :: Type
(Type
alphaTy:Type
betaTy:Type
gammaTy:Type
deltaTy:[Type]
_) = [Type]
alphaTys

alphaTyVarsUnliftedRep :: [TyVar]
alphaTyVarsUnliftedRep :: [TyVar]
alphaTyVarsUnliftedRep = [Type] -> [TyVar]
mkTemplateTyVars forall a b. (a -> b) -> a -> b
$ forall a. a -> [a]
repeat Type
unliftedTypeKind

alphaTyVarUnliftedRep :: TyVar
(TyVar
alphaTyVarUnliftedRep:[TyVar]
_) = [TyVar]
alphaTyVarsUnliftedRep

alphaTysUnliftedRep :: [Type]
alphaTysUnliftedRep :: [Type]
alphaTysUnliftedRep = [TyVar] -> [Type]
mkTyVarTys [TyVar]
alphaTyVarsUnliftedRep
alphaTyUnliftedRep :: Type
(Type
alphaTyUnliftedRep:[Type]
_) = [Type]
alphaTysUnliftedRep

runtimeRep1TyVar, runtimeRep2TyVar, runtimeRep3TyVar :: TyVar
(TyVar
runtimeRep1TyVar : TyVar
runtimeRep2TyVar : TyVar
runtimeRep3TyVar : [TyVar]
_)
  = forall a. Int -> [a] -> [a]
drop Int
16 ([Type] -> [TyVar]
mkTemplateTyVars (forall a. a -> [a]
repeat Type
runtimeRepTy))  -- selects 'q','r'

runtimeRep1TyVarInf, runtimeRep2TyVarInf :: TyVarBinder
runtimeRep1TyVarInf :: TyVarBinder
runtimeRep1TyVarInf = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Inferred TyVar
runtimeRep1TyVar
runtimeRep2TyVarInf :: TyVarBinder
runtimeRep2TyVarInf = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Inferred TyVar
runtimeRep2TyVar

runtimeRep1Ty, runtimeRep2Ty, runtimeRep3Ty :: RuntimeRepType
runtimeRep1Ty :: Type
runtimeRep1Ty = TyVar -> Type
mkTyVarTy TyVar
runtimeRep1TyVar
runtimeRep2Ty :: Type
runtimeRep2Ty = TyVar -> Type
mkTyVarTy TyVar
runtimeRep2TyVar
runtimeRep3Ty :: Type
runtimeRep3Ty = TyVar -> Type
mkTyVarTy TyVar
runtimeRep3TyVar
openAlphaTyVar, openBetaTyVar, openGammaTyVar :: TyVar
-- alpha :: TYPE r1
-- beta  :: TYPE r2
-- gamma :: TYPE r3
[TyVar
openAlphaTyVar,TyVar
openBetaTyVar,TyVar
openGammaTyVar]
  = [Type] -> [TyVar]
mkTemplateTyVars [ Type -> Type
mk_TYPE_app Type
runtimeRep1Ty
                     , Type -> Type
mk_TYPE_app Type
runtimeRep2Ty
                     , Type -> Type
mk_TYPE_app Type
runtimeRep3Ty]

openAlphaTyVarSpec, openBetaTyVarSpec, openGammaTyVarSpec :: TyVarBinder
openAlphaTyVarSpec :: TyVarBinder
openAlphaTyVarSpec = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Specified TyVar
openAlphaTyVar
openBetaTyVarSpec :: TyVarBinder
openBetaTyVarSpec  = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Specified TyVar
openBetaTyVar
openGammaTyVarSpec :: TyVarBinder
openGammaTyVarSpec = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Specified TyVar
openGammaTyVar

openAlphaTy, openBetaTy, openGammaTy :: Type
openAlphaTy :: Type
openAlphaTy = TyVar -> Type
mkTyVarTy TyVar
openAlphaTyVar
openBetaTy :: Type
openBetaTy  = TyVar -> Type
mkTyVarTy TyVar
openBetaTyVar
openGammaTy :: Type
openGammaTy = TyVar -> Type
mkTyVarTy TyVar
openGammaTyVar

levity1TyVar, levity2TyVar :: TyVar
(TyVar
levity2TyVar : TyVar
levity1TyVar : [TyVar]
_) -- NB: levity2TyVar before levity1TyVar
  = forall a. Int -> [a] -> [a]
drop Int
10 ([Type] -> [TyVar]
mkTemplateTyVars (forall a. a -> [a]
repeat Type
levityTy)) -- selects 'k', 'l'
-- The ordering of levity2TyVar before levity1TyVar is chosen so that
-- the more common levity1TyVar uses the levity variable 'l'.

levity1TyVarInf, levity2TyVarInf :: TyVarBinder
levity1TyVarInf :: TyVarBinder
levity1TyVarInf = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Inferred TyVar
levity1TyVar
levity2TyVarInf :: TyVarBinder
levity2TyVarInf = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Inferred TyVar
levity2TyVar

levity1Ty, levity2Ty :: Type
levity1Ty :: Type
levity1Ty = TyVar -> Type
mkTyVarTy TyVar
levity1TyVar
levity2Ty :: Type
levity2Ty = TyVar -> Type
mkTyVarTy TyVar
levity2TyVar

levPolyAlphaTyVar, levPolyBetaTyVar :: TyVar
[TyVar
levPolyAlphaTyVar, TyVar
levPolyBetaTyVar] =
  [Type] -> [TyVar]
mkTemplateTyVars
    [ Type -> Type
mk_TYPE_app (TyCon -> [Type] -> Type
mkTyConApp TyCon
boxedRepDataConTyCon [Type
levity1Ty])
    , Type -> Type
mk_TYPE_app (TyCon -> [Type] -> Type
mkTyConApp TyCon
boxedRepDataConTyCon [Type
levity2Ty])]
-- alpha :: TYPE ('BoxedRep l)
-- beta  :: TYPE ('BoxedRep k)

levPolyAlphaTyVarSpec, levPolyBetaTyVarSpec :: TyVarBinder
levPolyAlphaTyVarSpec :: TyVarBinder
levPolyAlphaTyVarSpec = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Specified TyVar
levPolyAlphaTyVar
levPolyBetaTyVarSpec :: TyVarBinder
levPolyBetaTyVarSpec  = forall vis. vis -> TyVar -> VarBndr TyVar vis
mkTyVarBinder ForAllTyFlag
Specified TyVar
levPolyBetaTyVar

levPolyAlphaTy, levPolyBetaTy :: Type
levPolyAlphaTy :: Type
levPolyAlphaTy = TyVar -> Type
mkTyVarTy TyVar
levPolyAlphaTyVar
levPolyBetaTy :: Type
levPolyBetaTy  = TyVar -> Type
mkTyVarTy TyVar
levPolyBetaTyVar

multiplicityTyVar1, multiplicityTyVar2  :: TyVar
(TyVar
multiplicityTyVar1 : TyVar
multiplicityTyVar2 : [TyVar]
_)
   = forall a. Int -> [a] -> [a]
drop Int
13 ([Type] -> [TyVar]
mkTemplateTyVars (forall a. a -> [a]
repeat Type
multiplicityTy))  -- selects 'n', 'm'


{-
************************************************************************
*                                                                      *
                FunTyCon
*                                                                      *
************************************************************************
-}

{- Note [Function type constructors and FunTy]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
We have four distinct function type constructors, and a type synonym

 FUN :: forall (m :: Multiplicity) ->
        forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
        TYPE rep1 -> TYPE rep2 -> Type

 (=>)  :: forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
          CONSTRAINT rep1 -> TYPE rep2 -> Type

 (==>) :: forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
          CONSTRAINT rep1 -> CONSTRAINT rep2 -> Constraint

 (-=>) :: forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
          TYPE rep1 -> CONSTRAINT rep2 -> Constraint

 type (->) = FUN Many

For efficiency, all four are always represented by
  FunTy { ft_af :: FunTyFlag, ft_mult :: Mult
        , ft_arg :: Type, ft_res :: Type }
rather than by using a TyConApp.

* The four TyCons FUN, (=>), (==>), (-=>) are all wired in.
  But (->) is just a regular synonym, with no special treatment;
  in particular it is not wired-in.

* The ft_af :: FunTyFlag distinguishes the four cases.
  See Note [FunTyFlag] in GHC.Types.Var.

* The ft_af field is redundant: it can always be gleaned from
  the kinds of ft_arg and ft_res.  See Note [FunTyFlag] in GHC.Types.Var.

* The ft_mult :: Mult field gives the first argument for FUN
  For the other three cases ft_mult is redundant; it is always Many.
  Note that of the four type constructors, only `FUN` takes a Multiplicity.

* Functions in GHC.Core.Type help to build and decompose `FunTy`.
  * funTyConAppTy_maybe
  * funTyFlagTyCon
  * tyConAppFun_maybe
  * splitFunTy_maybe
  Use them!
-}

funTyFlagTyCon :: FunTyFlag -> TyCon
-- `anonArgTyCon af` gets the TyCon that corresponds to the `FunTyFlag`
-- But be careful: fUNTyCon has a different kind to the others!
-- See Note [Function type constructors and FunTy]
funTyFlagTyCon :: FunTyFlag -> TyCon
funTyFlagTyCon FunTyFlag
FTF_T_T = TyCon
fUNTyCon
funTyFlagTyCon FunTyFlag
FTF_T_C = TyCon
tcArrowTyCon
funTyFlagTyCon FunTyFlag
FTF_C_T = TyCon
ctArrowTyCon
funTyFlagTyCon FunTyFlag
FTF_C_C = TyCon
ccArrowTyCon

isArrowTyCon :: TyCon -> Bool
-- We don't bother to look for plain (->), because this function
-- should only be used after unwrapping synonyms
isArrowTyCon :: TyCon -> Bool
isArrowTyCon TyCon
tc
  = forall a. HasCallStack => Bool -> SDoc -> a -> a
assertPpr (Bool -> Bool
not (TyCon -> Bool
isTypeSynonymTyCon TyCon
tc)) (forall a. Outputable a => a -> SDoc
ppr TyCon
tc)
    forall a. Uniquable a => a -> Unique
getUnique TyCon
tc forall (t :: * -> *) a. (Foldable t, Eq a) => a -> t a -> Bool
`elem`
    [Unique
fUNTyConKey, Unique
ctArrowTyConKey, Unique
ccArrowTyConKey, Unique
tcArrowTyConKey]

fUNTyConName, ctArrowTyConName, ccArrowTyConName, tcArrowTyConName :: Name
fUNTyConName :: Name
fUNTyConName     = FastString -> Unique -> TyCon -> Name
mkPrimTc        (String -> FastString
fsLit String
"FUN") Unique
fUNTyConKey       TyCon
fUNTyCon
ctArrowTyConName :: Name
ctArrowTyConName = FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc (String -> FastString
fsLit String
"=>")  Unique
ctArrowTyConKey TyCon
ctArrowTyCon
ccArrowTyConName :: Name
ccArrowTyConName = FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc (String -> FastString
fsLit String
"==>") Unique
ccArrowTyConKey TyCon
ccArrowTyCon
tcArrowTyConName :: Name
tcArrowTyConName = FastString -> Unique -> TyCon -> Name
mkBuiltInPrimTc (String -> FastString
fsLit String
"-=>") Unique
tcArrowTyConKey TyCon
tcArrowTyCon

-- | The @FUN@ type constructor.
--
-- @
-- FUN :: forall (m :: Multiplicity) ->
--        forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
--        TYPE rep1 -> TYPE rep2 -> Type
-- @
--
-- The runtime representations quantification is left inferred. This
-- means they cannot be specified with @-XTypeApplications@.
--
-- This is a deliberate choice to allow future extensions to the
-- function arrow.
fUNTyCon :: TyCon
fUNTyCon :: TyCon
fUNTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
fUNTyConName [TyConBinder]
tc_bndrs Type
liftedTypeKind [Role]
tc_roles
  where
    -- See also unrestrictedFunTyCon
    tc_bndrs :: [TyConBinder]
tc_bndrs = [ ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Required TyVar
multiplicityTyVar1
               , ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep1TyVar
               , ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep2TyVar ]
               forall a. [a] -> [a] -> [a]
++ [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [ Type -> Type
mk_TYPE_app Type
runtimeRep1Ty
                                             , Type -> Type
mk_TYPE_app Type
runtimeRep2Ty ]
    tc_roles :: [Role]
tc_roles = [Role
Nominal, Role
Nominal, Role
Nominal, Role
Representational, Role
Representational]

-- (=>) :: forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
--         CONSTRAINT rep1 -> TYPE rep2 -> Type
ctArrowTyCon :: TyCon
ctArrowTyCon :: TyCon
ctArrowTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
ctArrowTyConName [TyConBinder]
tc_bndrs Type
liftedTypeKind [Role]
tc_roles
  where
    -- See also unrestrictedFunTyCon
    tc_bndrs :: [TyConBinder]
tc_bndrs = [ ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep1TyVar
               , ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep2TyVar ]
               forall a. [a] -> [a] -> [a]
++ [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [ Type -> Type
mk_CONSTRAINT_app Type
runtimeRep1Ty
                                             , Type -> Type
mk_TYPE_app       Type
runtimeRep2Ty ]
    tc_roles :: [Role]
tc_roles = [Role
Nominal, Role
Nominal, Role
Representational, Role
Representational]

-- (==>) :: forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
--          CONSTRAINT rep1 -> CONSTRAINT rep2 -> Constraint
ccArrowTyCon :: TyCon
ccArrowTyCon :: TyCon
ccArrowTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
ccArrowTyConName [TyConBinder]
tc_bndrs Type
constraintKind [Role]
tc_roles
  where
    -- See also unrestrictedFunTyCon
    tc_bndrs :: [TyConBinder]
tc_bndrs = [ ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep1TyVar
               , ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep2TyVar ]
               forall a. [a] -> [a] -> [a]
++ [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [ Type -> Type
mk_CONSTRAINT_app Type
runtimeRep1Ty
                                             , Type -> Type
mk_CONSTRAINT_app Type
runtimeRep2Ty ]
    tc_roles :: [Role]
tc_roles = [Role
Nominal, Role
Nominal, Role
Representational, Role
Representational]

-- (-=>) :: forall {rep1 :: RuntimeRep} {rep2 :: RuntimeRep}.
--          TYPE rep1 -> CONSTRAINT rep2 -> Constraint
tcArrowTyCon :: TyCon
tcArrowTyCon :: TyCon
tcArrowTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
tcArrowTyConName [TyConBinder]
tc_bndrs Type
constraintKind [Role]
tc_roles
  where
    -- See also unrestrictedFunTyCon
    tc_bndrs :: [TyConBinder]
tc_bndrs = [ ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep1TyVar
               , ForAllTyFlag -> TyVar -> TyConBinder
mkNamedTyConBinder ForAllTyFlag
Inferred TyVar
runtimeRep2TyVar ]
               forall a. [a] -> [a] -> [a]
++ [Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [ Type -> Type
mk_TYPE_app       Type
runtimeRep1Ty
                                             , Type -> Type
mk_CONSTRAINT_app Type
runtimeRep2Ty ]
    tc_roles :: [Role]
tc_roles = [Role
Nominal, Role
Nominal, Role
Representational, Role
Representational]

{-
************************************************************************
*                                                                      *
                Type and Constraint
*                                                                      *
************************************************************************

Note [TYPE and CONSTRAINT]  aka Note [Type vs Constraint]
~~~~~~~~~~~~~~~~~~~~~~~~~~
GHC distinguishes Type from Constraint throughout the compiler.
See GHC Proposal #518, and tickets #21623 and #11715.

All types that classify values have a kind of the form
  (TYPE rr) or (CONSTRAINT rr)
where the `RuntimeRep` parameter, rr, tells us how the value is represented
at runtime.  TYPE and CONSTRAINT are primitive type constructors.

See Note [RuntimeRep polymorphism] about the `rr` parameter.

There are a bunch of type synonyms and data types defined in the
library ghc-prim:GHC.Types.  All of them are also wired in to GHC, in
GHC.Builtin.Types

  type Constraint   = CONSTRAINT LiftedRep  :: Type

  type Type         = TYPE LiftedRep   :: Type
  type UnliftedType = TYPE UnliftedRep :: Type

  type LiftedRep    = BoxedRep Lifted   :: RuntimeRep
  type UnliftedRep  = BoxedRep Unlifted :: RuntimeRep

  data RuntimeRep     -- Defined in ghc-prim:GHC.Types
      = BoxedRep Levity
      | IntRep
      | FloatRep
      .. etc ..

  data Levity = Lifted | Unlifted

We abbreviate '*' specially (with -XStarIsType), as if we had this:
    type * = Type

So for example:
    Int        :: TYPE (BoxedRep Lifted)
    Array# Int :: TYPE (BoxedRep Unlifted)
    Int#       :: TYPE IntRep
    Float#     :: TYPE FloatRep
    Maybe      :: TYPE (BoxedRep Lifted) -> TYPE (BoxedRep Lifted)
    (# , #)    :: TYPE r1 -> TYPE r2 -> TYPE (TupleRep [r1, r2])

    Eq Int       :: CONSTRAINT (BoxedRep Lifted)
    IP "foo" Int :: CONSTRAINT (BoxedRep Lifted)
    a ~ b        :: CONSTRAINT (BoxedRep Lifted)
    a ~# b       :: CONSTRAINT (TupleRep [])

Constraints are mostly lifted, but unlifted ones are useful too.
Specifically  (a ~# b) :: CONSTRAINT (TupleRep [])

Wrinkles

(W1) Type and Constraint are considered distinct throughout GHC. But they
     are not /apart/: see Note [Type and Constraint are not apart]

(W2) We need two absent-error Ids, aBSENT_ERROR_ID for types of kind Type, and
     aBSENT_CONSTRAINT_ERROR_ID for vaues of kind Constraint.  Ditto noInlineId
     vs noInlieConstraintId in GHC.Types.Id.Make; see Note [inlineId magic].

(W3) We need a TypeOrConstraint flag in LitRubbish.

Note [Type and Constraint are not apart]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Type and Constraint are not equal (eqType) but they are not /apart/
either. Reason (c.f. #7451):

* We want to allow newtype classes, where
    class C a where { op :: a -> a }

* The axiom for such a class will look like
    axiom axC a :: (C a :: Constraint) ~# (a->a :: Type)

* This axiom connects a type of kind Type with one of kind Constraint
  That is dangerous: kindCo (axC Int) :: Type ~N Constraint
  And /that/ is bad because we could have
     type family F a where
        F Type       = Int
        F Constraint = Bool
  So now we can prove Int ~N Bool, and all is lost.  We prevent this
  by saying that Type and Constraint are not Apart, which makes the
  above type family instances illegal.

So we ensure that Type and Constraint are not apart; or, more
precisely, that TYPE and CONSTRAINT are not apart.  This
non-apart-ness check is implemented in GHC.Core.Unify.unify_ty: look
for `maybeApart MARTypeVsConstraint`.

Note that, as before, nothing prevents writing instances like:

  instance C (Proxy @Type a) where ...

In particular, TYPE and CONSTRAINT (and the synonyms Type, Constraint
etc) are all allowed in instance heads. It's just that TYPE is not
apart from CONSTRAINT, which means that the above instance would
irretrievably overlap with:

  instance C (Proxy @Constraint a) where ...

Wrinkles

(W1) In GHC.Core.RoughMap.roughMtchTyConName we are careful to map
     TYPE and CONSTRAINT to the same rough-map key.  Reason:
     If we insert (F @Constraint tys) into a FamInstEnv, and look
     up (F @Type tys'), we /must/ ensure that the (C @Constraint tys)
     appears among the unifiables when we do the lookupRM' in
     GHC.Core.FamInstEnv.lookup_fam_inst_env'.  So for the RoughMap we
     simply pretend that they are the same type constructor.  If we
     don't, we'll treat them as fully apart, which is unsound.

(W2) We must extend this treatment to the different arrow types (see
     Note [Function type constructors and FunTy]): if we have
       FunCo (axC Int) <Int> :: (C Int => Int) ~ ((Int -> Int) -> Int),
     then we could extract an equality between (=>) and (->). We thus
     must ensure that (=>) and (->) (among the other arrow combinations)
     are not Apart. See the FunTy/FunTy case in GHC.Core.Unify.unify_ty.

(W3) Are (TYPE IntRep) and (CONSTRAINT WordRep) apart?  In truth yes,
     they are.  But it's easier to say that htey are not apart, by
     reporting "maybeApart" (which is always safe), rather than
     recurse into the arguments (whose kinds may be utterly different)
     to look for apartness inside them.  Again this is in
     GHC.Core.Unify.unify_ty.

(W4) We give a different Typeable instance for Type than for Constraint.
     For type classes instances (unlike type family instances) it is not
     /unsound/ for Type and Constraint to treated as fully distinct; and
     for Typeable is desirable to give them different TypeReps.
     Certainly,
       - both Type and Constraint must /have/ a TypeRep, and
       - they had better not be the same (else eqTypeRep would give us
         a proof Type ~N Constraint, which we do not want
     So in GHC.Tc.Instance.Class.matchTypeable, Type and Constraint are
     treated as separate TyCons; i.e. given no special treatment.

Note [RuntimeRep polymorphism]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Generally speaking, you can't be polymorphic in `RuntimeRep`.  E.g
   f :: forall (rr:RuntimeRep) (a:TYPE rr). a -> [a]
   f = /\(rr:RuntimeRep) (a:rr) \(a:rr). ...
This is no good: we could not generate code for 'f', because the
calling convention for 'f' varies depending on whether the argument is
a a Int, Int#, or Float#.  (You could imagine generating specialised
code, one for each instantiation of 'rr', but we don't do that.)

Certain functions CAN be runtime-rep-polymorphic, because the code
generator never has to manipulate a value of type 'a :: TYPE rr'.

* error :: forall (rr:RuntimeRep) (a:TYPE rr). String -> a
  Code generator never has to manipulate the return value.

* unsafeCoerce#, defined in Desugar.mkUnsafeCoercePair:
  Always inlined to be a no-op
     unsafeCoerce# :: forall (r1 :: RuntimeRep) (r2 :: RuntimeRep)
                             (a :: TYPE r1) (b :: TYPE r2).
                             a -> b

* Unboxed tuples, and unboxed sums, defined in GHC.Builtin.Types
  Always inlined, and hence specialised to the call site
     (#,#) :: forall (r1 :: RuntimeRep) (r2 :: RuntimeRep)
                     (a :: TYPE r1) (b :: TYPE r2).
                     a -> b -> TYPE ('TupleRep '[r1, r2])
-}

----------------------
tYPETyCon :: TyCon
tYPETyCon :: TyCon
tYPETyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
tYPETyConName
                        ([Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [Type
runtimeRepTy])
                        Type
liftedTypeKind
                        [Role
Nominal]

tYPETyConName :: Name
tYPETyConName :: Name
tYPETyConName = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"TYPE") Unique
tYPETyConKey TyCon
tYPETyCon

tYPEKind :: Type
tYPEKind :: Type
tYPEKind = TyCon -> Type
mkTyConTy TyCon
tYPETyCon

----------------------
cONSTRAINTTyCon :: TyCon
cONSTRAINTTyCon :: TyCon
cONSTRAINTTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
cONSTRAINTTyConName
                              ([Type] -> [TyConBinder]
mkTemplateAnonTyConBinders [Type
runtimeRepTy])
                              Type
liftedTypeKind
                              [Role
Nominal]

cONSTRAINTTyConName :: Name
cONSTRAINTTyConName :: Name
cONSTRAINTTyConName = FastString -> Unique -> TyCon -> Name
mkPrimTc (String -> FastString
fsLit String
"CONSTRAINT") Unique
cONSTRAINTTyConKey TyCon
cONSTRAINTTyCon

cONSTRAINTKind :: Type
cONSTRAINTKind :: Type
cONSTRAINTKind = TyCon -> Type
mkTyConTy TyCon
cONSTRAINTTyCon


{- *********************************************************************
*                                                                      *
       Basic primitive types (Char#, Int#, etc.)
*                                                                      *
********************************************************************* -}

charPrimTy :: Type
charPrimTy :: Type
charPrimTy      = TyCon -> Type
mkTyConTy TyCon
charPrimTyCon
charPrimTyCon :: TyCon
charPrimTyCon :: TyCon
charPrimTyCon   = Name -> Type -> TyCon
pcPrimTyCon0 Name
charPrimTyConName Type
wordRepDataConTy

intPrimTy :: Type
intPrimTy :: Type
intPrimTy       = TyCon -> Type
mkTyConTy TyCon
intPrimTyCon
intPrimTyCon :: TyCon
intPrimTyCon :: TyCon
intPrimTyCon    = Name -> Type -> TyCon
pcPrimTyCon0 Name
intPrimTyConName Type
intRepDataConTy

int8PrimTy :: Type
int8PrimTy :: Type
int8PrimTy     = TyCon -> Type
mkTyConTy TyCon
int8PrimTyCon
int8PrimTyCon :: TyCon
int8PrimTyCon :: TyCon
int8PrimTyCon  = Name -> Type -> TyCon
pcPrimTyCon0 Name
int8PrimTyConName Type
int8RepDataConTy

int16PrimTy :: Type
int16PrimTy :: Type
int16PrimTy    = TyCon -> Type
mkTyConTy TyCon
int16PrimTyCon
int16PrimTyCon :: TyCon
int16PrimTyCon :: TyCon
int16PrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
int16PrimTyConName Type
int16RepDataConTy

int32PrimTy :: Type
int32PrimTy :: Type
int32PrimTy     = TyCon -> Type
mkTyConTy TyCon
int32PrimTyCon
int32PrimTyCon :: TyCon
int32PrimTyCon :: TyCon
int32PrimTyCon  = Name -> Type -> TyCon
pcPrimTyCon0 Name
int32PrimTyConName Type
int32RepDataConTy

int64PrimTy :: Type
int64PrimTy :: Type
int64PrimTy     = TyCon -> Type
mkTyConTy TyCon
int64PrimTyCon
int64PrimTyCon :: TyCon
int64PrimTyCon :: TyCon
int64PrimTyCon  = Name -> Type -> TyCon
pcPrimTyCon0 Name
int64PrimTyConName Type
int64RepDataConTy

wordPrimTy :: Type
wordPrimTy :: Type
wordPrimTy      = TyCon -> Type
mkTyConTy TyCon
wordPrimTyCon
wordPrimTyCon :: TyCon
wordPrimTyCon :: TyCon
wordPrimTyCon   = Name -> Type -> TyCon
pcPrimTyCon0 Name
wordPrimTyConName Type
wordRepDataConTy

word8PrimTy :: Type
word8PrimTy :: Type
word8PrimTy     = TyCon -> Type
mkTyConTy TyCon
word8PrimTyCon
word8PrimTyCon :: TyCon
word8PrimTyCon :: TyCon
word8PrimTyCon  = Name -> Type -> TyCon
pcPrimTyCon0 Name
word8PrimTyConName Type
word8RepDataConTy

word16PrimTy :: Type
word16PrimTy :: Type
word16PrimTy    = TyCon -> Type
mkTyConTy TyCon
word16PrimTyCon
word16PrimTyCon :: TyCon
word16PrimTyCon :: TyCon
word16PrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
word16PrimTyConName Type
word16RepDataConTy

word32PrimTy :: Type
word32PrimTy :: Type
word32PrimTy    = TyCon -> Type
mkTyConTy TyCon
word32PrimTyCon
word32PrimTyCon :: TyCon
word32PrimTyCon :: TyCon
word32PrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
word32PrimTyConName Type
word32RepDataConTy

word64PrimTy :: Type
word64PrimTy :: Type
word64PrimTy    = TyCon -> Type
mkTyConTy TyCon
word64PrimTyCon
word64PrimTyCon :: TyCon
word64PrimTyCon :: TyCon
word64PrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
word64PrimTyConName Type
word64RepDataConTy

addrPrimTy :: Type
addrPrimTy :: Type
addrPrimTy      = TyCon -> Type
mkTyConTy TyCon
addrPrimTyCon
addrPrimTyCon :: TyCon
addrPrimTyCon :: TyCon
addrPrimTyCon   = Name -> Type -> TyCon
pcPrimTyCon0 Name
addrPrimTyConName Type
addrRepDataConTy

floatPrimTy     :: Type
floatPrimTy :: Type
floatPrimTy     = TyCon -> Type
mkTyConTy TyCon
floatPrimTyCon
floatPrimTyCon :: TyCon
floatPrimTyCon :: TyCon
floatPrimTyCon  = Name -> Type -> TyCon
pcPrimTyCon0 Name
floatPrimTyConName Type
floatRepDataConTy

doublePrimTy :: Type
doublePrimTy :: Type
doublePrimTy    = TyCon -> Type
mkTyConTy TyCon
doublePrimTyCon
doublePrimTyCon :: TyCon
doublePrimTyCon :: TyCon
doublePrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
doublePrimTyConName Type
doubleRepDataConTy

{-
************************************************************************
*                                                                      *
   The @State#@ type (and @_RealWorld@ types)
*                                                                      *
************************************************************************

Note [The equality types story]
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
GHC sports a veritable menagerie of equality types:

         Type or  Lifted?  Hetero?  Role      Built in         Defining module
         class?    L/U                        TyCon
-----------------------------------------------------------------------------------------
~#         T        U      hetero   nominal   eqPrimTyCon      GHC.Prim
~~         C        L      hetero   nominal   heqTyCon         GHC.Types
~          C        L      homo     nominal   eqTyCon          GHC.Types
:~:        T        L      homo     nominal   (not built-in)   Data.Type.Equality
:~~:       T        L      hetero   nominal   (not built-in)   Data.Type.Equality

~R#        T        U      hetero   repr      eqReprPrimTy     GHC.Prim
Coercible  C        L      homo     repr      coercibleTyCon   GHC.Types
Coercion   T        L      homo     repr      (not built-in)   Data.Type.Coercion
~P#        T        U      hetero   phantom   eqPhantPrimTyCon GHC.Prim

Recall that "hetero" means the equality can related types of different
kinds. Knowing that (t1 ~# t2) or (t1 ~R# t2) or even that (t1 ~P# t2)
also means that (k1 ~# k2), where (t1 :: k1) and (t2 :: k2).

To produce less confusion for end users, when not dumping and without
-fprint-equality-relations, each of these groups is printed as the bottommost
listed equality. That is, (~#) and (~~) are both rendered as (~) in
error messages, and (~R#) is rendered as Coercible.

Let's take these one at a time:

    --------------------------
    (~#) :: forall k1 k2. k1 -> k2 -> TYPE (TupleRep '[])
    --------------------------
This is The Type Of Equality in GHC. It classifies nominal coercions.
This type is used in the solver for recording equality constraints.
It responds "yes" to Type.isEqPrimPred and classifies as an EqPred in
Type.classifyPredType.

All wanted constraints of this type are built with coercion holes.
(See Note [Coercion holes] in GHC.Core.TyCo.Rep.) But see also
Note [Deferred errors for coercion holes] in GHC.Tc.Errors to see how
equality constraints are deferred.

Within GHC, ~# is called eqPrimTyCon, and it is defined in GHC.Builtin.Types.Prim.


    --------------------------
    (~~) :: forall k1 k2. k1 -> k2 -> Constraint
    --------------------------
This is (almost) an ordinary class, defined as if by
  class a ~# b => a ~~ b
  instance a ~# b => a ~~ b
Here's what's unusual about it:

 * We can't actually declare it that way because we don't have syntax for ~#.
   And ~# isn't a constraint, so even if we could write it, it wouldn't kind
   check.

 * Users cannot write instances of it.

 * It is "naturally coherent". This means that the solver won't hesitate to
   solve a goal of type (a ~~ b) even if there is, say (Int ~~ c) in the
   context. (Normally, it waits to learn more, just in case the given
   influences what happens next.) See Note [Naturally coherent classes]
   in GHC.Tc.Solver.Interact.

 * It always terminates. That is, in the UndecidableInstances checks, we
   don't worry if a (~~) constraint is too big, as we know that solving
   equality terminates.

On the other hand, this behaves just like any class w.r.t. eager superclass
unpacking in the solver. So a lifted equality given quickly becomes an unlifted
equality given. This is good, because the solver knows all about unlifted
equalities. There is some special-casing in GHC.Tc.Solver.Interact.matchClassInst to
pretend that there is an instance of this class, as we can't write the instance
in Haskell.

Within GHC, ~~ is called heqTyCon, and it is defined in GHC.Builtin.Types.


    --------------------------
    (~) :: forall k. k -> k -> Constraint
    --------------------------
This is /exactly/ like (~~), except with a homogeneous kind.
It is an almost-ordinary class defined as if by
  class a ~# b => (a :: k) ~ (b :: k)
  instance a ~# b => a ~ b

 * All the bullets for (~~) apply

 * In addition (~) is magical syntax, as ~ is a reserved symbol.
   It cannot be exported or imported.

 * The data constructor of the class is "Eq#", not ":C~"

Within GHC, ~ is called eqTyCon, and it is defined in GHC.Builtin.Types.

Historical note: prior to July 18 (~) was defined as a
  more-ordinary class with (~~) as a superclass.  But that made it
  special in different ways; and the extra superclass selections to
  get from (~) to (~#) via (~~) were tiresome.  Now it's defined
  uniformly with (~~) and Coercible; much nicer.)


    --------------------------
    (:~:) :: forall k. k -> k -> *
    (:~~:) :: forall k1 k2. k1 -> k2 -> *
    --------------------------
These are perfectly ordinary GADTs, wrapping (~) and (~~) resp.
They are not defined within GHC at all.


    --------------------------
    (~R#) :: forall k1 k2. k1 -> k2 -> TYPE (TupleRep '[])
    --------------------------
The is the representational analogue of ~#. This is the type of representational
equalities that the solver works on. All wanted constraints of this type are
built with coercion holes.

Within GHC, ~R# is called eqReprPrimTyCon, and it is defined in GHC.Builtin.Types.Prim.


    --------------------------
    Coercible :: forall k. k -> k -> Constraint
    --------------------------
This is quite like (~~) in the way it's defined and treated within GHC, but
it's homogeneous. Homogeneity helps with type inference (as GHC can solve one
kind from the other) and, in my (Richard's) estimation, will be more intuitive
for users.

An alternative design included HCoercible (like (~~)) and Coercible (like (~)).
One annoyance was that we want `coerce :: Coercible a b => a -> b`, and
we need the type of coerce to be fully wired-in. So the HCoercible/Coercible
split required that both types be fully wired-in. Instead of doing this,
I just got rid of HCoercible, as I'm not sure who would use it, anyway.

Within GHC, Coercible is called coercibleTyCon, and it is defined in
GHC.Builtin.Types.


    --------------------------
    Coercion :: forall k. k -> k -> *
    --------------------------
This is a perfectly ordinary GADT, wrapping Coercible. It is not defined
within GHC at all.


    --------------------------
    (~P#) :: forall k1 k2. k1 -> k2 -> TYPE (TupleRep '[])
    --------------------------
This is the phantom analogue of ~# and it is barely used at all.
(The solver has no idea about this one.) Here is the motivation:

    data Phant a = MkPhant
    type role Phant phantom

    Phant <Int, Bool>_P :: Phant Int ~P# Phant Bool

We just need to have something to put on that last line. You probably
don't need to worry about it.



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.
-}

mkStatePrimTy :: Type -> Type
mkStatePrimTy :: Type -> Type
mkStatePrimTy Type
ty = TyCon -> [Type] -> Type
TyConApp TyCon
statePrimTyCon [Type
ty]

statePrimTyCon :: TyCon   -- See Note [The State# TyCon]
statePrimTyCon :: TyCon
statePrimTyCon   = Name -> [Role] -> Type -> TyCon
pcPrimTyCon Name
statePrimTyConName [Role
Nominal] Type
zeroBitRepTy

{-
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#.
-}

realWorldTyCon :: TyCon
realWorldTyCon :: TyCon
realWorldTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
realWorldTyConName [] Type
liftedTypeKind []
realWorldTy :: Type
realWorldTy :: Type
realWorldTy          = TyCon -> Type
mkTyConTy TyCon
realWorldTyCon
realWorldStatePrimTy :: Type
realWorldStatePrimTy :: Type
realWorldStatePrimTy = Type -> Type
mkStatePrimTy Type
realWorldTy        -- State# RealWorld


mkProxyPrimTy :: Type -> Type -> Type
mkProxyPrimTy :: Type -> Type -> Type
mkProxyPrimTy Type
k Type
ty = TyCon -> [Type] -> Type
TyConApp TyCon
proxyPrimTyCon [Type
k, Type
ty]

proxyPrimTyCon :: TyCon
proxyPrimTyCon :: TyCon
proxyPrimTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
proxyPrimTyConName [TyConBinder]
binders Type
res_kind [Role
Nominal,Role
Phantom]
  where
     -- Kind: forall k. k -> TYPE (TupleRep '[])
     binders :: [TyConBinder]
binders = [Type] -> ([Type] -> [Type]) -> [TyConBinder]
mkTemplateTyConBinders [Type
liftedTypeKind] forall a. a -> a
id
     res_kind :: Type
res_kind = [Type] -> Type
unboxedTupleKind []


{- *********************************************************************
*                                                                      *
                Primitive equality constraints
    See Note [The equality types story]
*                                                                      *
********************************************************************* -}

eqPrimTyCon :: TyCon  -- The representation type for equality predicates
                      -- See Note [The equality types story]
eqPrimTyCon :: TyCon
eqPrimTyCon  = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
eqPrimTyConName [TyConBinder]
binders Type
res_kind [Role]
roles
  where
    -- Kind :: forall k1 k2. k1 -> k2 -> CONSTRAINT ZeroBitRep
    binders :: [TyConBinder]
binders  = [Type] -> ([Type] -> [Type]) -> [TyConBinder]
mkTemplateTyConBinders [Type
liftedTypeKind, Type
liftedTypeKind] forall a. a -> a
id
    res_kind :: Type
res_kind = TyCon -> [Type] -> Type
TyConApp TyCon
cONSTRAINTTyCon [Type
zeroBitRepTy]
    roles :: [Role]
roles    = [Role
Nominal, Role
Nominal, Role
Nominal, Role
Nominal]

-- like eqPrimTyCon, but the type for *Representational* coercions
-- this should only ever appear as the type of a covar. Its role is
-- interpreted in coercionRole
eqReprPrimTyCon :: TyCon   -- See Note [The equality types story]
eqReprPrimTyCon :: TyCon
eqReprPrimTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
eqReprPrimTyConName [TyConBinder]
binders Type
res_kind [Role]
roles
  where
    -- Kind :: forall k1 k2. k1 -> k2 -> CONSTRAINT ZeroBitRep
    binders :: [TyConBinder]
binders  = [Type] -> ([Type] -> [Type]) -> [TyConBinder]
mkTemplateTyConBinders [Type
liftedTypeKind, Type
liftedTypeKind] forall a. a -> a
id
    res_kind :: Type
res_kind = TyCon -> [Type] -> Type
TyConApp TyCon
cONSTRAINTTyCon [Type
zeroBitRepTy]
    roles :: [Role]
roles    = [Role
Nominal, Role
Nominal, Role
Representational, Role
Representational]

-- like eqPrimTyCon, but the type for *Phantom* coercions.
-- This is only used to make higher-order equalities. Nothing
-- should ever actually have this type!
eqPhantPrimTyCon :: TyCon
eqPhantPrimTyCon :: TyCon
eqPhantPrimTyCon = Name -> [TyConBinder] -> Type -> [Role] -> TyCon
mkPrimTyCon Name
eqPhantPrimTyConName [TyConBinder]
binders Type
res_kind [Role]
roles
  where
    -- Kind :: forall k1 k2. k1 -> k2 -> CONSTRAINT ZeroBitRep
    binders :: [TyConBinder]
binders  = [Type] -> ([Type] -> [Type]) -> [TyConBinder]
mkTemplateTyConBinders [Type
liftedTypeKind, Type
liftedTypeKind] forall a. a -> a
id
    res_kind :: Type
res_kind = TyCon -> [Type] -> Type
TyConApp TyCon
cONSTRAINTTyCon [Type
zeroBitRepTy]
    roles :: [Role]
roles    = [Role
Nominal, Role
Nominal, Role
Phantom, Role
Phantom]

-- | Given a Role, what TyCon is the type of equality predicates at that role?
equalityTyCon :: Role -> TyCon
equalityTyCon :: Role -> TyCon
equalityTyCon Role
Nominal          = TyCon
eqPrimTyCon
equalityTyCon Role
Representational = TyCon
eqReprPrimTyCon
equalityTyCon Role
Phantom          = TyCon
eqPhantPrimTyCon

{- *********************************************************************
*                                                                      *
             The primitive array types
*                                                                      *
********************************************************************* -}

arrayPrimTyCon, mutableArrayPrimTyCon, mutableByteArrayPrimTyCon,
    byteArrayPrimTyCon,
    smallArrayPrimTyCon, smallMutableArrayPrimTyCon :: TyCon
arrayPrimTyCon :: TyCon
arrayPrimTyCon             = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
arrayPrimTyConName        [Role
Representational]          Type
unliftedRepTy
mutableArrayPrimTyCon :: TyCon
mutableArrayPrimTyCon      = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
mutableArrayPrimTyConName [Role
Nominal, Role
Representational] Type
unliftedRepTy
mutableByteArrayPrimTyCon :: TyCon
mutableByteArrayPrimTyCon  = Name -> [Role] -> Type -> TyCon
pcPrimTyCon Name
mutableByteArrayPrimTyConName  [Role
Nominal] Type
unliftedRepTy
byteArrayPrimTyCon :: TyCon
byteArrayPrimTyCon         = Name -> Type -> TyCon
pcPrimTyCon0 Name
byteArrayPrimTyConName        Type
unliftedRepTy
smallArrayPrimTyCon :: TyCon
smallArrayPrimTyCon        = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
smallArrayPrimTyConName        [Role
Representational]          Type
unliftedRepTy
smallMutableArrayPrimTyCon :: TyCon
smallMutableArrayPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
smallMutableArrayPrimTyConName [Role
Nominal, Role
Representational] Type
unliftedRepTy

mkArrayPrimTy :: Type -> Type
mkArrayPrimTy :: Type -> Type
mkArrayPrimTy Type
elt           = TyCon -> [Type] -> Type
TyConApp TyCon
arrayPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
elt]
byteArrayPrimTy :: Type
byteArrayPrimTy :: Type
byteArrayPrimTy             = TyCon -> Type
mkTyConTy TyCon
byteArrayPrimTyCon
mkSmallArrayPrimTy :: Type -> Type
mkSmallArrayPrimTy :: Type -> Type
mkSmallArrayPrimTy Type
elt = TyCon -> [Type] -> Type
TyConApp TyCon
smallArrayPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
elt]
mkMutableArrayPrimTy :: Type -> Type -> Type
mkMutableArrayPrimTy :: Type -> Type -> Type
mkMutableArrayPrimTy Type
s Type
elt  = TyCon -> [Type] -> Type
TyConApp TyCon
mutableArrayPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
s, Type
elt]
mkMutableByteArrayPrimTy :: Type -> Type
mkMutableByteArrayPrimTy :: Type -> Type
mkMutableByteArrayPrimTy Type
s  = TyCon -> [Type] -> Type
TyConApp TyCon
mutableByteArrayPrimTyCon [Type
s]
mkSmallMutableArrayPrimTy :: Type -> Type -> Type
mkSmallMutableArrayPrimTy :: Type -> Type -> Type
mkSmallMutableArrayPrimTy Type
s Type
elt = TyCon -> [Type] -> Type
TyConApp TyCon
smallMutableArrayPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
s, Type
elt]


{- *********************************************************************
*                                                                      *
                The mutable variable type
*                                                                      *
********************************************************************* -}

mutVarPrimTyCon :: TyCon
mutVarPrimTyCon :: TyCon
mutVarPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
mutVarPrimTyConName [Role
Nominal, Role
Representational] Type
unliftedRepTy

mkMutVarPrimTy :: Type -> Type -> Type
mkMutVarPrimTy :: Type -> Type -> Type
mkMutVarPrimTy Type
s Type
elt        = TyCon -> [Type] -> Type
TyConApp TyCon
mutVarPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
s, Type
elt]

{-
************************************************************************
*                                                                      *
\subsection[TysPrim-io-port-var]{The synchronizing I/O Port type}
*                                                                      *
************************************************************************
-}

ioPortPrimTyCon :: TyCon
ioPortPrimTyCon :: TyCon
ioPortPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
ioPortPrimTyConName [Role
Nominal, Role
Representational] Type
unliftedRepTy

mkIOPortPrimTy :: Type -> Type -> Type
mkIOPortPrimTy :: Type -> Type -> Type
mkIOPortPrimTy Type
s Type
elt          = TyCon -> [Type] -> Type
TyConApp TyCon
ioPortPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
s, Type
elt]

{-
************************************************************************
*                                                                      *
   The synchronizing variable type
\subsection[TysPrim-synch-var]{The synchronizing variable type}
*                                                                      *
************************************************************************
-}

mVarPrimTyCon :: TyCon
mVarPrimTyCon :: TyCon
mVarPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
mVarPrimTyConName [Role
Nominal, Role
Representational] Type
unliftedRepTy

mkMVarPrimTy :: Type -> Type -> Type
mkMVarPrimTy :: Type -> Type -> Type
mkMVarPrimTy Type
s Type
elt          = TyCon -> [Type] -> Type
TyConApp TyCon
mVarPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
s, Type
elt]

{-
************************************************************************
*                                                                      *
   The transactional variable type
*                                                                      *
************************************************************************
-}

tVarPrimTyCon :: TyCon
tVarPrimTyCon :: TyCon
tVarPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
tVarPrimTyConName [Role
Nominal, Role
Representational] Type
unliftedRepTy

mkTVarPrimTy :: Type -> Type -> Type
mkTVarPrimTy :: Type -> Type -> Type
mkTVarPrimTy Type
s Type
elt = TyCon -> [Type] -> Type
TyConApp TyCon
tVarPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
elt, Type
s, Type
elt]

{-
************************************************************************
*                                                                      *
   The stable-pointer type
*                                                                      *
************************************************************************
-}

stablePtrPrimTyCon :: TyCon
stablePtrPrimTyCon :: TyCon
stablePtrPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
stablePtrPrimTyConName [Role
Representational] Type
addrRepDataConTy

mkStablePtrPrimTy :: Type -> Type
mkStablePtrPrimTy :: Type -> Type
mkStablePtrPrimTy Type
ty = TyCon -> [Type] -> Type
TyConApp TyCon
stablePtrPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
ty, Type
ty]

{-
************************************************************************
*                                                                      *
   The stable-name type
*                                                                      *
************************************************************************
-}

stableNamePrimTyCon :: TyCon
stableNamePrimTyCon :: TyCon
stableNamePrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
stableNamePrimTyConName [Role
Phantom] Type
unliftedRepTy

mkStableNamePrimTy :: Type -> Type
mkStableNamePrimTy :: Type -> Type
mkStableNamePrimTy Type
ty = TyCon -> [Type] -> Type
TyConApp TyCon
stableNamePrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
ty, Type
ty]

{-
************************************************************************
*                                                                      *
   The Compact NFData (CNF) type
*                                                                      *
************************************************************************
-}

compactPrimTyCon :: TyCon
compactPrimTyCon :: TyCon
compactPrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
compactPrimTyConName Type
unliftedRepTy

compactPrimTy :: Type
compactPrimTy :: Type
compactPrimTy = TyCon -> Type
mkTyConTy TyCon
compactPrimTyCon

{-
************************************************************************
*                                                                      *
   The @StackSnapshot#@ type
*                                                                      *
************************************************************************
-}

stackSnapshotPrimTyCon :: TyCon
stackSnapshotPrimTyCon :: TyCon
stackSnapshotPrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
stackSnapshotPrimTyConName Type
unliftedRepTy

stackSnapshotPrimTy :: Type
stackSnapshotPrimTy :: Type
stackSnapshotPrimTy = TyCon -> Type
mkTyConTy TyCon
stackSnapshotPrimTyCon


{-
************************************************************************
*                                                                      *
   The ``bytecode object'' type
*                                                                      *
************************************************************************
-}

-- Unlike most other primitive types, BCO is lifted. This is because in
-- general a BCO may be a thunk for the reasons given in Note [Updatable CAF
-- BCOs] in GHCi.CreateBCO.
bcoPrimTy    :: Type
bcoPrimTy :: Type
bcoPrimTy    = TyCon -> Type
mkTyConTy TyCon
bcoPrimTyCon
bcoPrimTyCon :: TyCon
bcoPrimTyCon :: TyCon
bcoPrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
bcoPrimTyConName Type
liftedRepTy

{-
************************************************************************
*                                                                      *
   The ``weak pointer'' type
*                                                                      *
************************************************************************
-}

weakPrimTyCon :: TyCon
weakPrimTyCon :: TyCon
weakPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon_LevPolyLastArg Name
weakPrimTyConName [Role
Representational] Type
unliftedRepTy

mkWeakPrimTy :: Type -> Type
mkWeakPrimTy :: Type -> Type
mkWeakPrimTy Type
v = TyCon -> [Type] -> Type
TyConApp TyCon
weakPrimTyCon [HasDebugCallStack => Type -> Type
getLevity Type
v, Type
v]

{-
************************************************************************
*                                                                      *
   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.
-}

threadIdPrimTy :: Type
threadIdPrimTy :: Type
threadIdPrimTy    = TyCon -> Type
mkTyConTy TyCon
threadIdPrimTyCon
threadIdPrimTyCon :: TyCon
threadIdPrimTyCon :: TyCon
threadIdPrimTyCon = Name -> Type -> TyCon
pcPrimTyCon0 Name
threadIdPrimTyConName Type
unliftedRepTy

{-
************************************************************************
*                                                                      *
   The ``prompt tag'' type
*                                                                      *
************************************************************************
-}

promptTagPrimTyCon :: TyCon
promptTagPrimTyCon :: TyCon
promptTagPrimTyCon = Name -> [Role] -> Type -> TyCon
pcPrimTyCon Name
promptTagPrimTyConName [Role
Representational] Type
unliftedRepTy

mkPromptTagPrimTy :: Type -> Type
mkPromptTagPrimTy :: Type -> Type
mkPromptTagPrimTy Type
v = TyCon -> [Type] -> Type
TyConApp TyCon
promptTagPrimTyCon [Type
v]

{-
************************************************************************
*                                                                      *
\subsection{SIMD vector types}
*                                                                      *
************************************************************************
-}

#include "primop-vector-tys.hs-incl"