{- (c) The GRASP Project, Glasgow University, 1994-1998 \section[TysWiredIn]{Wired-in knowledge about {\em non-primitive} types} -} {-# LANGUAGE CPP #-} {-# LANGUAGE OverloadedStrings #-} -- | This module is about types that can be defined in Haskell, but which -- must be wired into the compiler nonetheless. C.f module TysPrim module TysWiredIn ( -- * Helper functions defined here mkWiredInTyConName, -- This is used in TcTypeNats to define the -- built-in functions for evaluation. mkWiredInIdName, -- used in MkId mkFunKind, mkForAllKind, -- * All wired in things wiredInTyCons, isBuiltInOcc_maybe, -- * Bool boolTy, boolTyCon, boolTyCon_RDR, boolTyConName, trueDataCon, trueDataConId, true_RDR, falseDataCon, falseDataConId, false_RDR, promotedFalseDataCon, promotedTrueDataCon, -- * Ordering orderingTyCon, ltDataCon, ltDataConId, eqDataCon, eqDataConId, gtDataCon, gtDataConId, promotedLTDataCon, promotedEQDataCon, promotedGTDataCon, -- * Boxing primitive types boxingDataCon_maybe, -- * Char charTyCon, charDataCon, charTyCon_RDR, charTy, stringTy, charTyConName, -- * Double doubleTyCon, doubleDataCon, doubleTy, doubleTyConName, -- * Float floatTyCon, floatDataCon, floatTy, floatTyConName, -- * Int intTyCon, intDataCon, intTyCon_RDR, intDataCon_RDR, intTyConName, intTy, -- * Word wordTyCon, wordDataCon, wordTyConName, wordTy, -- * Word8 word8TyCon, word8DataCon, word8TyConName, word8Ty, -- * List listTyCon, listTyCon_RDR, listTyConName, listTyConKey, nilDataCon, nilDataConName, nilDataConKey, consDataCon_RDR, consDataCon, consDataConName, promotedNilDataCon, promotedConsDataCon, mkListTy, mkPromotedListTy, -- * Maybe maybeTyCon, maybeTyConName, nothingDataCon, nothingDataConName, promotedNothingDataCon, justDataCon, justDataConName, promotedJustDataCon, -- * Tuples mkTupleTy, mkBoxedTupleTy, tupleTyCon, tupleDataCon, tupleTyConName, promotedTupleDataCon, unitTyCon, unitDataCon, unitDataConId, unitTy, unitTyConKey, pairTyCon, unboxedUnitTyCon, unboxedUnitDataCon, unboxedTupleKind, unboxedSumKind, -- ** Constraint tuples cTupleTyConName, cTupleTyConNames, isCTupleTyConName, cTupleDataConName, cTupleDataConNames, -- * Any anyTyCon, anyTy, anyTypeOfKind, -- * Sums mkSumTy, sumTyCon, sumDataCon, -- * Kinds typeNatKindCon, typeNatKind, typeSymbolKindCon, typeSymbolKind, isLiftedTypeKindTyConName, liftedTypeKind, constraintKind, starKindTyCon, starKindTyConName, unicodeStarKindTyCon, unicodeStarKindTyConName, liftedTypeKindTyCon, constraintKindTyCon, -- * Equality predicates heqTyCon, heqClass, heqDataCon, coercibleTyCon, coercibleTyConName, coercibleDataCon, coercibleClass, -- * RuntimeRep and friends runtimeRepTyCon, vecCountTyCon, vecElemTyCon, runtimeRepTy, liftedRepTy, liftedRepDataCon, liftedRepDataConTyCon, vecRepDataConTyCon, tupleRepDataConTyCon, sumRepDataConTyCon, liftedRepDataConTy, unliftedRepDataConTy, intRepDataConTy, wordRepDataConTy, int64RepDataConTy, word64RepDataConTy, addrRepDataConTy, floatRepDataConTy, doubleRepDataConTy, vec2DataConTy, vec4DataConTy, vec8DataConTy, vec16DataConTy, vec32DataConTy, vec64DataConTy, int8ElemRepDataConTy, int16ElemRepDataConTy, int32ElemRepDataConTy, int64ElemRepDataConTy, word8ElemRepDataConTy, word16ElemRepDataConTy, word32ElemRepDataConTy, word64ElemRepDataConTy, floatElemRepDataConTy, doubleElemRepDataConTy ) where #include "HsVersions.h" #include "MachDeps.h" import GhcPrelude import {-# SOURCE #-} MkId( mkDataConWorkId, mkDictSelId ) -- friends: import PrelNames import TysPrim import {-# SOURCE #-} KnownUniques -- others: import CoAxiom import Id import Constants ( mAX_TUPLE_SIZE, mAX_CTUPLE_SIZE, mAX_SUM_SIZE ) import Module ( Module ) import Type import RepType import DataCon import {-# SOURCE #-} ConLike import TyCon import Class ( Class, mkClass ) import RdrName import Name import NameEnv ( NameEnv, mkNameEnv, lookupNameEnv, lookupNameEnv_NF ) import NameSet ( NameSet, mkNameSet, elemNameSet ) import BasicTypes ( Arity, Boxity(..), TupleSort(..), ConTagZ, SourceText(..) ) import ForeignCall import SrcLoc ( noSrcSpan ) import Unique import Data.Array import FastString import Outputable import Util import BooleanFormula ( mkAnd ) import qualified Data.ByteString.Char8 as BS alpha_tyvar :: [TyVar] alpha_tyvar = [alphaTyVar] alpha_ty :: [Type] alpha_ty = [alphaTy] {- Note [Wiring in RuntimeRep] ~~~~~~~~~~~~~~~~~~~~~~~~~~~ The RuntimeRep type (and friends) in GHC.Types has a bunch of constructors, making it a pain to wire in. To ease the pain somewhat, we use lists of the different bits, like Uniques, Names, DataCons. These lists must be kept in sync with each other. The rule is this: use the order as declared in GHC.Types. All places where such lists exist should contain a reference to this Note, so a search for this Note's name should find all the lists. ************************************************************************ * * \subsection{Wired in type constructors} * * ************************************************************************ If you change which things are wired in, make sure you change their names in PrelNames, so they use wTcQual, wDataQual, etc -} -- This list is used only to define PrelInfo.wiredInThings. That in turn -- is used to initialise the name environment carried around by the renamer. -- This means that if we look up the name of a TyCon (or its implicit binders) -- that occurs in this list that name will be assigned the wired-in key we -- define here. -- -- Because of their infinite nature, this list excludes tuples, Any and implicit -- parameter TyCons (see Note [Built-in syntax and the OrigNameCache]). -- -- See also Note [Known-key names] wiredInTyCons :: [TyCon] wiredInTyCons = [ -- Units are not treated like other tuples, because then -- are defined in GHC.Base, and there's only a few of them. We -- put them in wiredInTyCons so that they will pre-populate -- the name cache, so the parser in isBuiltInOcc_maybe doesn't -- need to look out for them. unitTyCon , unboxedUnitTyCon , anyTyCon , boolTyCon , charTyCon , doubleTyCon , floatTyCon , intTyCon , wordTyCon , word8TyCon , listTyCon , maybeTyCon , heqTyCon , coercibleTyCon , typeNatKindCon , typeSymbolKindCon , runtimeRepTyCon , vecCountTyCon , vecElemTyCon , constraintKindTyCon , liftedTypeKindTyCon , starKindTyCon , unicodeStarKindTyCon ] mkWiredInTyConName :: BuiltInSyntax -> Module -> FastString -> Unique -> TyCon -> Name mkWiredInTyConName built_in modu fs unique tycon = mkWiredInName modu (mkTcOccFS fs) unique (ATyCon tycon) -- Relevant TyCon built_in mkWiredInDataConName :: BuiltInSyntax -> Module -> FastString -> Unique -> DataCon -> Name mkWiredInDataConName built_in modu fs unique datacon = mkWiredInName modu (mkDataOccFS fs) unique (AConLike (RealDataCon datacon)) -- Relevant DataCon built_in mkWiredInIdName :: Module -> FastString -> Unique -> Id -> Name mkWiredInIdName mod fs uniq id = mkWiredInName mod (mkOccNameFS Name.varName fs) uniq (AnId id) UserSyntax -- See Note [Kind-changing of (~) and Coercible] -- in libraries/ghc-prim/GHC/Types.hs heqTyConName, heqDataConName, heqSCSelIdName :: Name heqTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "~~") heqTyConKey heqTyCon heqDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "Eq#") heqDataConKey heqDataCon heqSCSelIdName = mkWiredInIdName gHC_TYPES (fsLit "heq_sel") heqSCSelIdKey heqSCSelId -- See Note [Kind-changing of (~) and Coercible] in libraries/ghc-prim/GHC/Types.hs coercibleTyConName, coercibleDataConName, coercibleSCSelIdName :: Name coercibleTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Coercible") coercibleTyConKey coercibleTyCon coercibleDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "MkCoercible") coercibleDataConKey coercibleDataCon coercibleSCSelIdName = mkWiredInIdName gHC_TYPES (fsLit "coercible_sel") coercibleSCSelIdKey coercibleSCSelId charTyConName, charDataConName, intTyConName, intDataConName :: Name charTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Char") charTyConKey charTyCon charDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "C#") charDataConKey charDataCon intTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Int") intTyConKey intTyCon intDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "I#") intDataConKey intDataCon boolTyConName, falseDataConName, trueDataConName :: Name boolTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Bool") boolTyConKey boolTyCon falseDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "False") falseDataConKey falseDataCon trueDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "True") trueDataConKey trueDataCon listTyConName, nilDataConName, consDataConName :: Name listTyConName = mkWiredInTyConName BuiltInSyntax gHC_TYPES (fsLit "[]") listTyConKey listTyCon nilDataConName = mkWiredInDataConName BuiltInSyntax gHC_TYPES (fsLit "[]") nilDataConKey nilDataCon consDataConName = mkWiredInDataConName BuiltInSyntax gHC_TYPES (fsLit ":") consDataConKey consDataCon maybeTyConName, nothingDataConName, justDataConName :: Name maybeTyConName = mkWiredInTyConName UserSyntax gHC_BASE (fsLit "Maybe") maybeTyConKey maybeTyCon nothingDataConName = mkWiredInDataConName UserSyntax gHC_BASE (fsLit "Nothing") nothingDataConKey nothingDataCon justDataConName = mkWiredInDataConName UserSyntax gHC_BASE (fsLit "Just") justDataConKey justDataCon wordTyConName, wordDataConName, word8TyConName, word8DataConName :: Name wordTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Word") wordTyConKey wordTyCon wordDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "W#") wordDataConKey wordDataCon word8TyConName = mkWiredInTyConName UserSyntax gHC_WORD (fsLit "Word8") word8TyConKey word8TyCon word8DataConName = mkWiredInDataConName UserSyntax gHC_WORD (fsLit "W8#") word8DataConKey word8DataCon floatTyConName, floatDataConName, doubleTyConName, doubleDataConName :: Name floatTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Float") floatTyConKey floatTyCon floatDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "F#") floatDataConKey floatDataCon doubleTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Double") doubleTyConKey doubleTyCon doubleDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "D#") doubleDataConKey doubleDataCon -- Any {- Note [Any types] ~~~~~~~~~~~~~~~~ The type constructor Any, type family Any :: k where { } It has these properties: * Note that 'Any' is kind polymorphic since in some program we may need to use Any to fill in a type variable of some kind other than * (see #959 for examples). Its kind is thus `forall k. k``. * It is defined in module GHC.Types, and exported so that it is available to users. For this reason it's treated like any other wired-in 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. See also #9097 and #9636. * When instantiated at a lifted type it is inhabited by at least one value, namely bottom * You can safely coerce any /lifted/ type to Any, and back with unsafeCoerce. * 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 wired-in so we can easily refer to it where we don't have a name environment (e.g. see Rules.matchRule for one example) * If (Any k) is the type of a value, it must be a /lifted/ value. So if we have (Any @(TYPE rr)) then rr must be 'LiftedRep. See Note [TYPE and RuntimeRep] in TysPrim. This is a convenient invariant, and makes isUnliftedTyCon well-defined; otherwise what would (isUnliftedTyCon Any) be? It's used to instantiate un-constrained type variables after type checking. For example, 'length' has type length :: forall a. [a] -> Int and the list datacon for the empty list has type [] :: forall a. [a] In order to compose these two terms as @length []@ a type application is required, but there is no constraint on the choice. In this situation GHC uses 'Any', > length (Any *) ([] (Any *)) Above, we print kinds explicitly, as if with --fprint-explicit-kinds. The Any tycon used to be quite magic, but we have since been able to implement it merely with an empty kind polymorphic type family. See #10886 for a bit of history. -} anyTyConName :: Name anyTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Any") anyTyConKey anyTyCon anyTyCon :: TyCon anyTyCon = mkFamilyTyCon anyTyConName binders res_kind Nothing (ClosedSynFamilyTyCon Nothing) Nothing NotInjective where binders@[kv] = mkTemplateKindTyConBinders [liftedTypeKind] res_kind = mkTyVarTy (binderVar kv) anyTy :: Type anyTy = mkTyConTy anyTyCon anyTypeOfKind :: Kind -> Type anyTypeOfKind kind = mkTyConApp anyTyCon [kind] -- Kinds typeNatKindConName, typeSymbolKindConName :: Name typeNatKindConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Nat") typeNatKindConNameKey typeNatKindCon typeSymbolKindConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Symbol") typeSymbolKindConNameKey typeSymbolKindCon constraintKindTyConName :: Name constraintKindTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Constraint") constraintKindTyConKey constraintKindTyCon liftedTypeKindTyConName, starKindTyConName, unicodeStarKindTyConName :: Name liftedTypeKindTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "Type") liftedTypeKindTyConKey liftedTypeKindTyCon starKindTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "*") starKindTyConKey starKindTyCon unicodeStarKindTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "★") unicodeStarKindTyConKey unicodeStarKindTyCon runtimeRepTyConName, vecRepDataConName, tupleRepDataConName, sumRepDataConName :: Name runtimeRepTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "RuntimeRep") runtimeRepTyConKey runtimeRepTyCon vecRepDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "VecRep") vecRepDataConKey vecRepDataCon tupleRepDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "TupleRep") tupleRepDataConKey tupleRepDataCon sumRepDataConName = mkWiredInDataConName UserSyntax gHC_TYPES (fsLit "SumRep") sumRepDataConKey sumRepDataCon -- See Note [Wiring in RuntimeRep] runtimeRepSimpleDataConNames :: [Name] runtimeRepSimpleDataConNames = zipWith3Lazy mk_special_dc_name [ fsLit "LiftedRep", fsLit "UnliftedRep" , fsLit "IntRep" , fsLit "WordRep", fsLit "Int64Rep", fsLit "Word64Rep" , fsLit "AddrRep", fsLit "FloatRep", fsLit "DoubleRep" ] runtimeRepSimpleDataConKeys runtimeRepSimpleDataCons vecCountTyConName :: Name vecCountTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "VecCount") vecCountTyConKey vecCountTyCon -- See Note [Wiring in RuntimeRep] vecCountDataConNames :: [Name] vecCountDataConNames = zipWith3Lazy mk_special_dc_name [ fsLit "Vec2", fsLit "Vec4", fsLit "Vec8" , fsLit "Vec16", fsLit "Vec32", fsLit "Vec64" ] vecCountDataConKeys vecCountDataCons vecElemTyConName :: Name vecElemTyConName = mkWiredInTyConName UserSyntax gHC_TYPES (fsLit "VecElem") vecElemTyConKey vecElemTyCon -- See Note [Wiring in RuntimeRep] vecElemDataConNames :: [Name] vecElemDataConNames = zipWith3Lazy mk_special_dc_name [ fsLit "Int8ElemRep", fsLit "Int16ElemRep", fsLit "Int32ElemRep" , fsLit "Int64ElemRep", fsLit "Word8ElemRep", fsLit "Word16ElemRep" , fsLit "Word32ElemRep", fsLit "Word64ElemRep" , fsLit "FloatElemRep", fsLit "DoubleElemRep" ] vecElemDataConKeys vecElemDataCons mk_special_dc_name :: FastString -> Unique -> DataCon -> Name mk_special_dc_name fs u dc = mkWiredInDataConName UserSyntax gHC_TYPES fs u dc boolTyCon_RDR, false_RDR, true_RDR, intTyCon_RDR, charTyCon_RDR, intDataCon_RDR, listTyCon_RDR, consDataCon_RDR :: RdrName boolTyCon_RDR = nameRdrName boolTyConName false_RDR = nameRdrName falseDataConName true_RDR = nameRdrName trueDataConName intTyCon_RDR = nameRdrName intTyConName charTyCon_RDR = nameRdrName charTyConName intDataCon_RDR = nameRdrName intDataConName listTyCon_RDR = nameRdrName listTyConName consDataCon_RDR = nameRdrName consDataConName {- ************************************************************************ * * \subsection{mkWiredInTyCon} * * ************************************************************************ -} -- This function assumes that the types it creates have all parameters at -- Representational role, and that there is no kind polymorphism. pcTyCon :: Name -> Maybe CType -> [TyVar] -> [DataCon] -> TyCon pcTyCon name cType tyvars cons = mkAlgTyCon name (mkAnonTyConBinders tyvars) liftedTypeKind (map (const Representational) tyvars) cType [] -- No stupid theta (mkDataTyConRhs cons) (VanillaAlgTyCon (mkPrelTyConRepName name)) False -- Not in GADT syntax pcDataCon :: Name -> [TyVar] -> [Type] -> TyCon -> DataCon pcDataCon n univs = pcDataConWithFixity False n univs [] -- no ex_tvs univs -- the univs are precisely the user-written tyvars pcDataConWithFixity :: Bool -- ^ declared infix? -> Name -- ^ datacon name -> [TyVar] -- ^ univ tyvars -> [TyVar] -- ^ ex tyvars -> [TyVar] -- ^ user-written tyvars -> [Type] -- ^ args -> TyCon -> DataCon pcDataConWithFixity infx n = pcDataConWithFixity' infx n (dataConWorkerUnique (nameUnique n)) NoRRI -- The Name's unique is the first of two free uniques; -- the first is used for the datacon itself, -- the second is used for the "worker name" -- -- To support this the mkPreludeDataConUnique function "allocates" -- one DataCon unique per pair of Ints. pcDataConWithFixity' :: Bool -> Name -> Unique -> RuntimeRepInfo -> [TyVar] -> [TyVar] -> [TyVar] -> [Type] -> TyCon -> DataCon -- The Name should be in the DataName name space; it's the name -- of the DataCon itself. pcDataConWithFixity' declared_infix dc_name wrk_key rri tyvars ex_tyvars user_tyvars arg_tys tycon = data_con where tag_map = mkTyConTagMap tycon -- This constructs the constructor Name to ConTag map once per -- constructor, which is quadratic. It's OK here, because it's -- only called for wired in data types that don't have a lot of -- constructors. It's also likely that GHC will lift tag_map, since -- we call pcDataConWithFixity' with static TyCons in the same module. -- See Note [Constructor tag allocation] and #14657 data_con = mkDataCon dc_name declared_infix prom_info (map (const no_bang) arg_tys) [] -- No labelled fields tyvars ex_tyvars (mkTyVarBinders Specified user_tyvars) [] -- No equality spec [] -- No theta arg_tys (mkTyConApp tycon (mkTyVarTys tyvars)) rri tycon (lookupNameEnv_NF tag_map dc_name) [] -- No stupid theta (mkDataConWorkId wrk_name data_con) NoDataConRep -- Wired-in types are too simple to need wrappers no_bang = HsSrcBang NoSourceText NoSrcUnpack NoSrcStrict wrk_name = mkDataConWorkerName data_con wrk_key prom_info = mkPrelTyConRepName dc_name mkDataConWorkerName :: DataCon -> Unique -> Name mkDataConWorkerName data_con wrk_key = mkWiredInName modu wrk_occ wrk_key (AnId (dataConWorkId data_con)) UserSyntax where modu = ASSERT( isExternalName dc_name ) nameModule dc_name dc_name = dataConName data_con dc_occ = nameOccName dc_name wrk_occ = mkDataConWorkerOcc dc_occ -- used for RuntimeRep and friends pcSpecialDataCon :: Name -> [Type] -> TyCon -> RuntimeRepInfo -> DataCon pcSpecialDataCon dc_name arg_tys tycon rri = pcDataConWithFixity' False dc_name (dataConWorkerUnique (nameUnique dc_name)) rri [] [] [] arg_tys tycon {- ************************************************************************ * * Kinds * * ************************************************************************ -} typeNatKindCon, typeSymbolKindCon :: TyCon -- data Nat -- data Symbol typeNatKindCon = pcTyCon typeNatKindConName Nothing [] [] typeSymbolKindCon = pcTyCon typeSymbolKindConName Nothing [] [] typeNatKind, typeSymbolKind :: Kind typeNatKind = mkTyConTy typeNatKindCon typeSymbolKind = mkTyConTy typeSymbolKindCon constraintKindTyCon :: TyCon constraintKindTyCon = pcTyCon constraintKindTyConName Nothing [] [] liftedTypeKind, constraintKind :: Kind liftedTypeKind = tYPE liftedRepTy constraintKind = mkTyConApp constraintKindTyCon [] -- mkFunKind and mkForAllKind are defined here -- solely so that TyCon can use them via a SOURCE import mkFunKind :: Kind -> Kind -> Kind mkFunKind = mkFunTy mkForAllKind :: TyVar -> ArgFlag -> Kind -> Kind mkForAllKind = mkForAllTy {- ************************************************************************ * * Stuff for dealing with tuples * * ************************************************************************ Note [How tuples work] See also Note [Known-key names] in PrelNames ~~~~~~~~~~~~~~~~~~~~~~ * There are three families of tuple TyCons and corresponding DataCons, expressed by the type BasicTypes.TupleSort: data TupleSort = BoxedTuple | UnboxedTuple | ConstraintTuple * All three families are AlgTyCons, whose AlgTyConRhs is TupleTyCon * BoxedTuples - A wired-in type - Data type declarations in GHC.Tuple - The data constructors really have an info table * UnboxedTuples - A wired-in type - Have a pretend DataCon, defined in GHC.Prim, but no actual declaration and no info table * ConstraintTuples - Are known-key rather than wired-in. Reason: it's awkward to have all the superclass selectors wired-in. - Declared as classes in GHC.Classes, e.g. class (c1,c2) => (c1,c2) - Given constraints: the superclasses automatically become available - Wanted constraints: there is a built-in instance instance (c1,c2) => (c1,c2) See TcInteract.matchCTuple - Currently just go up to 62; beyond that you have to use manual nesting - Their OccNames look like (%,,,%), so they can easily be distinguished from term tuples. But (following Haskell) we pretty-print saturated constraint tuples with round parens; see BasicTypes.tupleParens. * In quite a lot of places things are restrcted just to BoxedTuple/UnboxedTuple, and then we used BasicTypes.Boxity to distinguish E.g. tupleTyCon has a Boxity argument * When looking up an OccName in the original-name cache (IfaceEnv.lookupOrigNameCache), we spot the tuple OccName to make sure we get the right wired-in name. This guy can't tell the difference between BoxedTuple and ConstraintTuple (same OccName!), so tuples are not serialised into interface files using OccNames at all. * Serialization to interface files works via the usual mechanism for known-key things: instead of serializing the OccName we just serialize the key. During deserialization we lookup the Name associated with the unique with the logic in KnownUniques. See Note [Symbol table representation of names] for details. Note [One-tuples] ~~~~~~~~~~~~~~~~~ GHC supports both boxed and unboxed one-tuples: - Unboxed one-tuples are sometimes useful when returning a single value after CPR analysis - A boxed one-tuple is used by DsUtils.mkSelectorBinds, when there is just one binder Basically it keeps everythig uniform. However the /naming/ of the type/data constructors for one-tuples is a bit odd: 3-tuples: (,,) (,,)# 2-tuples: (,) (,)# 1-tuples: ?? 0-tuples: () ()# Zero-tuples have used up the logical name. So we use 'Unit' and 'Unit#' for one-tuples. So in ghc-prim:GHC.Tuple we see the declarations: data () = () data Unit a = Unit a data (a,b) = (a,b) NB (Feb 16): for /constraint/ one-tuples I have 'Unit%' but no class decl in GHC.Classes, so I think this part may not work properly. But it's unused I think. -} -- | Built-in syntax isn't "in scope" so these OccNames map to wired-in Names -- with BuiltInSyntax. However, this should only be necessary while resolving -- names produced by Template Haskell splices since we take care to encode -- built-in syntax names specially in interface files. See -- Note [Symbol table representation of names]. -- -- Moreover, there is no need to include names of things that the user can't -- write (e.g. type representation bindings like $tc(,,,)). isBuiltInOcc_maybe :: OccName -> Maybe Name isBuiltInOcc_maybe occ = case name of "[]" -> Just $ choose_ns listTyConName nilDataConName ":" -> Just consDataConName -- boxed tuple data/tycon "()" -> Just $ tup_name Boxed 0 _ | Just rest <- "(" `BS.stripPrefix` name , (commas, rest') <- BS.span (==',') rest , ")" <- rest' -> Just $ tup_name Boxed (1+BS.length commas) -- unboxed tuple data/tycon "(##)" -> Just $ tup_name Unboxed 0 "Unit#" -> Just $ tup_name Unboxed 1 _ | Just rest <- "(#" `BS.stripPrefix` name , (commas, rest') <- BS.span (==',') rest , "#)" <- rest' -> Just $ tup_name Unboxed (1+BS.length commas) -- unboxed sum tycon _ | Just rest <- "(#" `BS.stripPrefix` name , (pipes, rest') <- BS.span (=='|') rest , "#)" <- rest' -> Just $ tyConName $ sumTyCon (1+BS.length pipes) -- unboxed sum datacon _ | Just rest <- "(#" `BS.stripPrefix` name , (pipes1, rest') <- BS.span (=='|') rest , Just rest'' <- "_" `BS.stripPrefix` rest' , (pipes2, rest''') <- BS.span (=='|') rest'' , "#)" <- rest''' -> let arity = BS.length pipes1 + BS.length pipes2 + 1 alt = BS.length pipes1 + 1 in Just $ dataConName $ sumDataCon alt arity _ -> Nothing where name = fastStringToByteString $ occNameFS occ choose_ns :: Name -> Name -> Name choose_ns tc dc | isTcClsNameSpace ns = tc | isDataConNameSpace ns = dc | otherwise = pprPanic "tup_name" (ppr occ) where ns = occNameSpace occ tup_name boxity arity = choose_ns (getName (tupleTyCon boxity arity)) (getName (tupleDataCon boxity arity)) mkTupleOcc :: NameSpace -> Boxity -> Arity -> OccName -- No need to cache these, the caching is done in mk_tuple mkTupleOcc ns Boxed ar = mkOccName ns (mkBoxedTupleStr ar) mkTupleOcc ns Unboxed ar = mkOccName ns (mkUnboxedTupleStr ar) mkCTupleOcc :: NameSpace -> Arity -> OccName mkCTupleOcc ns ar = mkOccName ns (mkConstraintTupleStr ar) mkBoxedTupleStr :: Arity -> String mkBoxedTupleStr 0 = "()" mkBoxedTupleStr 1 = "Unit" -- See Note [One-tuples] mkBoxedTupleStr ar = '(' : commas ar ++ ")" mkUnboxedTupleStr :: Arity -> String mkUnboxedTupleStr 0 = "(##)" mkUnboxedTupleStr 1 = "Unit#" -- See Note [One-tuples] mkUnboxedTupleStr ar = "(#" ++ commas ar ++ "#)" mkConstraintTupleStr :: Arity -> String mkConstraintTupleStr 0 = "(%%)" mkConstraintTupleStr 1 = "Unit%" -- See Note [One-tuples] mkConstraintTupleStr ar = "(%" ++ commas ar ++ "%)" commas :: Arity -> String commas ar = take (ar-1) (repeat ',') cTupleTyConName :: Arity -> Name cTupleTyConName arity = mkExternalName (mkCTupleTyConUnique arity) gHC_CLASSES (mkCTupleOcc tcName arity) noSrcSpan cTupleTyConNames :: [Name] cTupleTyConNames = map cTupleTyConName (0 : [2..mAX_CTUPLE_SIZE]) cTupleTyConNameSet :: NameSet cTupleTyConNameSet = mkNameSet cTupleTyConNames isCTupleTyConName :: Name -> Bool -- Use Type.isCTupleClass where possible isCTupleTyConName n = ASSERT2( isExternalName n, ppr n ) nameModule n == gHC_CLASSES && n `elemNameSet` cTupleTyConNameSet cTupleDataConName :: Arity -> Name cTupleDataConName arity = mkExternalName (mkCTupleDataConUnique arity) gHC_CLASSES (mkCTupleOcc dataName arity) noSrcSpan cTupleDataConNames :: [Name] cTupleDataConNames = map cTupleDataConName (0 : [2..mAX_CTUPLE_SIZE]) tupleTyCon :: Boxity -> Arity -> TyCon tupleTyCon sort i | i > mAX_TUPLE_SIZE = fst (mk_tuple sort i) -- Build one specially tupleTyCon Boxed i = fst (boxedTupleArr ! i) tupleTyCon Unboxed i = fst (unboxedTupleArr ! i) tupleTyConName :: TupleSort -> Arity -> Name tupleTyConName ConstraintTuple a = cTupleTyConName a tupleTyConName BoxedTuple a = tyConName (tupleTyCon Boxed a) tupleTyConName UnboxedTuple a = tyConName (tupleTyCon Unboxed a) promotedTupleDataCon :: Boxity -> Arity -> TyCon promotedTupleDataCon boxity i = promoteDataCon (tupleDataCon boxity i) tupleDataCon :: Boxity -> Arity -> DataCon tupleDataCon sort i | i > mAX_TUPLE_SIZE = snd (mk_tuple sort i) -- Build one specially tupleDataCon Boxed i = snd (boxedTupleArr ! i) tupleDataCon Unboxed i = snd (unboxedTupleArr ! i) boxedTupleArr, unboxedTupleArr :: Array Int (TyCon,DataCon) boxedTupleArr = listArray (0,mAX_TUPLE_SIZE) [mk_tuple Boxed i | i <- [0..mAX_TUPLE_SIZE]] unboxedTupleArr = listArray (0,mAX_TUPLE_SIZE) [mk_tuple Unboxed i | i <- [0..mAX_TUPLE_SIZE]] -- | Given the TupleRep/SumRep tycon and list of RuntimeReps of the unboxed -- tuple/sum arguments, produces the return kind of an unboxed tuple/sum type -- constructor. @unboxedTupleSumKind [IntRep, LiftedRep] --> TYPE (TupleRep/SumRep -- [IntRep, LiftedRep])@ unboxedTupleSumKind :: TyCon -> [Type] -> Kind unboxedTupleSumKind tc rr_tys = tYPE (mkTyConApp tc [mkPromotedListTy runtimeRepTy rr_tys]) -- | Specialization of 'unboxedTupleSumKind' for tuples unboxedTupleKind :: [Type] -> Kind unboxedTupleKind = unboxedTupleSumKind tupleRepDataConTyCon mk_tuple :: Boxity -> Int -> (TyCon,DataCon) mk_tuple Boxed arity = (tycon, tuple_con) where tycon = mkTupleTyCon tc_name tc_binders tc_res_kind tc_arity tuple_con BoxedTuple flavour tc_binders = mkTemplateAnonTyConBinders (nOfThem arity liftedTypeKind) tc_res_kind = liftedTypeKind tc_arity = arity flavour = VanillaAlgTyCon (mkPrelTyConRepName tc_name) dc_tvs = binderVars tc_binders dc_arg_tys = mkTyVarTys dc_tvs tuple_con = pcDataCon dc_name dc_tvs dc_arg_tys tycon boxity = Boxed modu = gHC_TUPLE tc_name = mkWiredInName modu (mkTupleOcc tcName boxity arity) tc_uniq (ATyCon tycon) BuiltInSyntax dc_name = mkWiredInName modu (mkTupleOcc dataName boxity arity) dc_uniq (AConLike (RealDataCon tuple_con)) BuiltInSyntax tc_uniq = mkTupleTyConUnique boxity arity dc_uniq = mkTupleDataConUnique boxity arity mk_tuple Unboxed arity = (tycon, tuple_con) where tycon = mkTupleTyCon tc_name tc_binders tc_res_kind tc_arity tuple_con UnboxedTuple flavour -- See Note [Unboxed tuple RuntimeRep vars] in TyCon -- Kind: forall (k1:RuntimeRep) (k2:RuntimeRep). TYPE k1 -> TYPE k2 -> # tc_binders = mkTemplateTyConBinders (nOfThem arity runtimeRepTy) (\ks -> map tYPE ks) tc_res_kind = unboxedTupleKind rr_tys tc_arity = arity * 2 flavour = UnboxedAlgTyCon $ Just (mkPrelTyConRepName tc_name) dc_tvs = binderVars tc_binders (rr_tys, dc_arg_tys) = splitAt arity (mkTyVarTys dc_tvs) tuple_con = pcDataCon dc_name dc_tvs dc_arg_tys tycon boxity = Unboxed modu = gHC_PRIM tc_name = mkWiredInName modu (mkTupleOcc tcName boxity arity) tc_uniq (ATyCon tycon) BuiltInSyntax dc_name = mkWiredInName modu (mkTupleOcc dataName boxity arity) dc_uniq (AConLike (RealDataCon tuple_con)) BuiltInSyntax tc_uniq = mkTupleTyConUnique boxity arity dc_uniq = mkTupleDataConUnique boxity arity unitTyCon :: TyCon unitTyCon = tupleTyCon Boxed 0 unitTyConKey :: Unique unitTyConKey = getUnique unitTyCon unitDataCon :: DataCon unitDataCon = head (tyConDataCons unitTyCon) unitDataConId :: Id unitDataConId = dataConWorkId unitDataCon pairTyCon :: TyCon pairTyCon = tupleTyCon Boxed 2 unboxedUnitTyCon :: TyCon unboxedUnitTyCon = tupleTyCon Unboxed 0 unboxedUnitDataCon :: DataCon unboxedUnitDataCon = tupleDataCon Unboxed 0 {- ********************************************************************* * * Unboxed sums * * ********************************************************************* -} -- | OccName for n-ary unboxed sum type constructor. mkSumTyConOcc :: Arity -> OccName mkSumTyConOcc n = mkOccName tcName str where -- No need to cache these, the caching is done in mk_sum str = '(' : '#' : bars ++ "#)" bars = replicate (n-1) '|' -- | OccName for i-th alternative of n-ary unboxed sum data constructor. mkSumDataConOcc :: ConTag -> Arity -> OccName mkSumDataConOcc alt n = mkOccName dataName str where -- No need to cache these, the caching is done in mk_sum str = '(' : '#' : bars alt ++ '_' : bars (n - alt - 1) ++ "#)" bars i = replicate i '|' -- | Type constructor for n-ary unboxed sum. sumTyCon :: Arity -> TyCon sumTyCon arity | arity > mAX_SUM_SIZE = fst (mk_sum arity) -- Build one specially | arity < 2 = panic ("sumTyCon: Arity starts from 2. (arity: " ++ show arity ++ ")") | otherwise = fst (unboxedSumArr ! arity) -- | Data constructor for i-th alternative of a n-ary unboxed sum. sumDataCon :: ConTag -- Alternative -> Arity -- Arity -> DataCon sumDataCon alt arity | alt > arity = panic ("sumDataCon: index out of bounds: alt: " ++ show alt ++ " > arity " ++ show arity) | alt <= 0 = panic ("sumDataCon: Alts start from 1. (alt: " ++ show alt ++ ", arity: " ++ show arity ++ ")") | arity < 2 = panic ("sumDataCon: Arity starts from 2. (alt: " ++ show alt ++ ", arity: " ++ show arity ++ ")") | arity > mAX_SUM_SIZE = snd (mk_sum arity) ! (alt - 1) -- Build one specially | otherwise = snd (unboxedSumArr ! arity) ! (alt - 1) -- | Cached type and data constructors for sums. The outer array is -- indexed by the arity of the sum and the inner array is indexed by -- the alternative. unboxedSumArr :: Array Int (TyCon, Array Int DataCon) unboxedSumArr = listArray (2,mAX_SUM_SIZE) [mk_sum i | i <- [2..mAX_SUM_SIZE]] -- | Specialization of 'unboxedTupleSumKind' for sums unboxedSumKind :: [Type] -> Kind unboxedSumKind = unboxedTupleSumKind sumRepDataConTyCon -- | Create type constructor and data constructors for n-ary unboxed sum. mk_sum :: Arity -> (TyCon, Array ConTagZ DataCon) mk_sum arity = (tycon, sum_cons) where tycon = mkSumTyCon tc_name tc_binders tc_res_kind (arity * 2) tyvars (elems sum_cons) (UnboxedAlgTyCon rep_name) -- Unboxed sums are currently not Typeable due to efficiency concerns. See #13276. rep_name = Nothing -- Just $ mkPrelTyConRepName tc_name tc_binders = mkTemplateTyConBinders (nOfThem arity runtimeRepTy) (\ks -> map tYPE ks) tyvars = binderVars tc_binders tc_res_kind = unboxedSumKind rr_tys (rr_tys, tyvar_tys) = splitAt arity (mkTyVarTys tyvars) tc_name = mkWiredInName gHC_PRIM (mkSumTyConOcc arity) tc_uniq (ATyCon tycon) BuiltInSyntax sum_cons = listArray (0,arity-1) [sum_con i | i <- [0..arity-1]] sum_con i = let dc = pcDataCon dc_name tyvars -- univ tyvars [tyvar_tys !! i] -- arg types tycon dc_name = mkWiredInName gHC_PRIM (mkSumDataConOcc i arity) (dc_uniq i) (AConLike (RealDataCon dc)) BuiltInSyntax in dc tc_uniq = mkSumTyConUnique arity dc_uniq i = mkSumDataConUnique i arity {- ************************************************************************ * * Equality types and classes * * ********************************************************************* -} -- See Note [The equality types story] in TysPrim -- ((~~) :: forall k1 k2 (a :: k1) (b :: k2). a -> b -> Constraint) -- -- It's tempting to put functional dependencies on (~~), but it's not -- necessary because the functional-dependency coverage check looks -- through superclasses, and (~#) is handled in that check. heqTyCon, coercibleTyCon :: TyCon heqClass, coercibleClass :: Class heqDataCon, coercibleDataCon :: DataCon heqSCSelId, coercibleSCSelId :: Id (heqTyCon, heqClass, heqDataCon, heqSCSelId) = (tycon, klass, datacon, sc_sel_id) where tycon = mkClassTyCon heqTyConName binders roles rhs klass (mkPrelTyConRepName heqTyConName) klass = mk_class tycon sc_pred sc_sel_id datacon = pcDataCon heqDataConName tvs [sc_pred] tycon -- Kind: forall k1 k2. k1 -> k2 -> Constraint binders = mkTemplateTyConBinders [liftedTypeKind, liftedTypeKind] (\ks -> ks) roles = [Nominal, Nominal, Nominal, Nominal] rhs = mkDataTyConRhs [datacon] tvs = binderVars binders sc_pred = mkTyConApp eqPrimTyCon (mkTyVarTys tvs) sc_sel_id = mkDictSelId heqSCSelIdName klass (coercibleTyCon, coercibleClass, coercibleDataCon, coercibleSCSelId) = (tycon, klass, datacon, sc_sel_id) where tycon = mkClassTyCon coercibleTyConName binders roles rhs klass (mkPrelTyConRepName coercibleTyConName) klass = mk_class tycon sc_pred sc_sel_id datacon = pcDataCon coercibleDataConName tvs [sc_pred] tycon -- Kind: forall k. k -> k -> Constraint binders = mkTemplateTyConBinders [liftedTypeKind] (\[k] -> [k,k]) roles = [Nominal, Representational, Representational] rhs = mkDataTyConRhs [datacon] tvs@[k,a,b] = binderVars binders sc_pred = mkTyConApp eqReprPrimTyCon (mkTyVarTys [k, k, a, b]) sc_sel_id = mkDictSelId coercibleSCSelIdName klass mk_class :: TyCon -> PredType -> Id -> Class mk_class tycon sc_pred sc_sel_id = mkClass (tyConName tycon) (tyConTyVars tycon) [] [sc_pred] [sc_sel_id] [] [] (mkAnd []) tycon {- ********************************************************************* * * Kinds and RuntimeRep * * ********************************************************************* -} -- For information about the usage of the following type, -- see Note [TYPE and RuntimeRep] in module TysPrim runtimeRepTy :: Type runtimeRepTy = mkTyConTy runtimeRepTyCon liftedTypeKindTyCon, starKindTyCon, unicodeStarKindTyCon :: TyCon -- Type synonyms; see Note [TYPE and RuntimeRep] in TysPrim -- type Type = tYPE 'LiftedRep -- type * = tYPE 'LiftedRep -- type * = tYPE 'LiftedRep -- Unicode variant liftedTypeKindTyCon = buildSynTyCon liftedTypeKindTyConName [] liftedTypeKind [] (tYPE liftedRepTy) starKindTyCon = buildSynTyCon starKindTyConName [] liftedTypeKind [] (tYPE liftedRepTy) unicodeStarKindTyCon = buildSynTyCon unicodeStarKindTyConName [] liftedTypeKind [] (tYPE liftedRepTy) runtimeRepTyCon :: TyCon runtimeRepTyCon = pcTyCon runtimeRepTyConName Nothing [] (vecRepDataCon : tupleRepDataCon : sumRepDataCon : runtimeRepSimpleDataCons) vecRepDataCon :: DataCon vecRepDataCon = pcSpecialDataCon vecRepDataConName [ mkTyConTy vecCountTyCon , mkTyConTy vecElemTyCon ] runtimeRepTyCon (RuntimeRep prim_rep_fun) where prim_rep_fun [count, elem] | VecCount n <- tyConRuntimeRepInfo (tyConAppTyCon count) , VecElem e <- tyConRuntimeRepInfo (tyConAppTyCon elem) = [VecRep n e] prim_rep_fun args = pprPanic "vecRepDataCon" (ppr args) vecRepDataConTyCon :: TyCon vecRepDataConTyCon = promoteDataCon vecRepDataCon tupleRepDataCon :: DataCon tupleRepDataCon = pcSpecialDataCon tupleRepDataConName [ mkListTy runtimeRepTy ] runtimeRepTyCon (RuntimeRep prim_rep_fun) where prim_rep_fun [rr_ty_list] = concatMap (runtimeRepPrimRep doc) rr_tys where rr_tys = extractPromotedList rr_ty_list doc = text "tupleRepDataCon" <+> ppr rr_tys prim_rep_fun args = pprPanic "tupleRepDataCon" (ppr args) tupleRepDataConTyCon :: TyCon tupleRepDataConTyCon = promoteDataCon tupleRepDataCon sumRepDataCon :: DataCon sumRepDataCon = pcSpecialDataCon sumRepDataConName [ mkListTy runtimeRepTy ] runtimeRepTyCon (RuntimeRep prim_rep_fun) where prim_rep_fun [rr_ty_list] = map slotPrimRep (ubxSumRepType prim_repss) where rr_tys = extractPromotedList rr_ty_list doc = text "sumRepDataCon" <+> ppr rr_tys prim_repss = map (runtimeRepPrimRep doc) rr_tys prim_rep_fun args = pprPanic "sumRepDataCon" (ppr args) sumRepDataConTyCon :: TyCon sumRepDataConTyCon = promoteDataCon sumRepDataCon -- See Note [Wiring in RuntimeRep] runtimeRepSimpleDataCons :: [DataCon] liftedRepDataCon :: DataCon runtimeRepSimpleDataCons@(liftedRepDataCon : _) = zipWithLazy mk_runtime_rep_dc [ LiftedRep, UnliftedRep, IntRep, WordRep, Int64Rep , Word64Rep, AddrRep, FloatRep, DoubleRep ] runtimeRepSimpleDataConNames where mk_runtime_rep_dc primrep name = pcSpecialDataCon name [] runtimeRepTyCon (RuntimeRep (\_ -> [primrep])) -- See Note [Wiring in RuntimeRep] liftedRepDataConTy, unliftedRepDataConTy, intRepDataConTy, wordRepDataConTy, int64RepDataConTy, word64RepDataConTy, addrRepDataConTy, floatRepDataConTy, doubleRepDataConTy :: Type [liftedRepDataConTy, unliftedRepDataConTy, intRepDataConTy, wordRepDataConTy, int64RepDataConTy, word64RepDataConTy, addrRepDataConTy, floatRepDataConTy, doubleRepDataConTy] = map (mkTyConTy . promoteDataCon) runtimeRepSimpleDataCons vecCountTyCon :: TyCon vecCountTyCon = pcTyCon vecCountTyConName Nothing [] vecCountDataCons -- See Note [Wiring in RuntimeRep] vecCountDataCons :: [DataCon] vecCountDataCons = zipWithLazy mk_vec_count_dc [ 2, 4, 8, 16, 32, 64 ] vecCountDataConNames where mk_vec_count_dc n name = pcSpecialDataCon name [] vecCountTyCon (VecCount n) -- See Note [Wiring in RuntimeRep] vec2DataConTy, vec4DataConTy, vec8DataConTy, vec16DataConTy, vec32DataConTy, vec64DataConTy :: Type [vec2DataConTy, vec4DataConTy, vec8DataConTy, vec16DataConTy, vec32DataConTy, vec64DataConTy] = map (mkTyConTy . promoteDataCon) vecCountDataCons vecElemTyCon :: TyCon vecElemTyCon = pcTyCon vecElemTyConName Nothing [] vecElemDataCons -- See Note [Wiring in RuntimeRep] vecElemDataCons :: [DataCon] vecElemDataCons = zipWithLazy mk_vec_elem_dc [ Int8ElemRep, Int16ElemRep, Int32ElemRep, Int64ElemRep , Word8ElemRep, Word16ElemRep, Word32ElemRep, Word64ElemRep , FloatElemRep, DoubleElemRep ] vecElemDataConNames where mk_vec_elem_dc elem name = pcSpecialDataCon name [] vecElemTyCon (VecElem elem) -- See Note [Wiring in RuntimeRep] int8ElemRepDataConTy, int16ElemRepDataConTy, int32ElemRepDataConTy, int64ElemRepDataConTy, word8ElemRepDataConTy, word16ElemRepDataConTy, word32ElemRepDataConTy, word64ElemRepDataConTy, floatElemRepDataConTy, doubleElemRepDataConTy :: Type [int8ElemRepDataConTy, int16ElemRepDataConTy, int32ElemRepDataConTy, int64ElemRepDataConTy, word8ElemRepDataConTy, word16ElemRepDataConTy, word32ElemRepDataConTy, word64ElemRepDataConTy, floatElemRepDataConTy, doubleElemRepDataConTy] = map (mkTyConTy . promoteDataCon) vecElemDataCons liftedRepDataConTyCon :: TyCon liftedRepDataConTyCon = promoteDataCon liftedRepDataCon -- The type ('LiftedRep) liftedRepTy :: Type liftedRepTy = mkTyConTy liftedRepDataConTyCon {- ********************************************************************* * * The boxed primitive types: Char, Int, etc * * ********************************************************************* -} boxingDataCon_maybe :: TyCon -> Maybe DataCon -- boxingDataCon_maybe Char# = C# -- boxingDataCon_maybe Int# = I# -- ... etc ... -- See Note [Boxing primitive types] boxingDataCon_maybe tc = lookupNameEnv boxing_constr_env (tyConName tc) boxing_constr_env :: NameEnv DataCon boxing_constr_env = mkNameEnv [(charPrimTyConName , charDataCon ) ,(intPrimTyConName , intDataCon ) ,(wordPrimTyConName , wordDataCon ) ,(floatPrimTyConName , floatDataCon ) ,(doublePrimTyConName, doubleDataCon) ] {- Note [Boxing primitive types] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ For a handful of primitive types (Int, Char, Word, Flaot, Double), we can readily box and an unboxed version (Int#, Char# etc) using the corresponding data constructor. This is useful in a couple of places, notably let-floating -} charTy :: Type charTy = mkTyConTy charTyCon charTyCon :: TyCon charTyCon = pcTyCon charTyConName (Just (CType NoSourceText Nothing (NoSourceText,fsLit "HsChar"))) [] [charDataCon] charDataCon :: DataCon charDataCon = pcDataCon charDataConName [] [charPrimTy] charTyCon stringTy :: Type stringTy = mkListTy charTy -- convenience only intTy :: Type intTy = mkTyConTy intTyCon intTyCon :: TyCon intTyCon = pcTyCon intTyConName (Just (CType NoSourceText Nothing (NoSourceText,fsLit "HsInt"))) [] [intDataCon] intDataCon :: DataCon intDataCon = pcDataCon intDataConName [] [intPrimTy] intTyCon wordTy :: Type wordTy = mkTyConTy wordTyCon wordTyCon :: TyCon wordTyCon = pcTyCon wordTyConName (Just (CType NoSourceText Nothing (NoSourceText, fsLit "HsWord"))) [] [wordDataCon] wordDataCon :: DataCon wordDataCon = pcDataCon wordDataConName [] [wordPrimTy] wordTyCon word8Ty :: Type word8Ty = mkTyConTy word8TyCon word8TyCon :: TyCon word8TyCon = pcTyCon word8TyConName (Just (CType NoSourceText Nothing (NoSourceText, fsLit "HsWord8"))) [] [word8DataCon] word8DataCon :: DataCon word8DataCon = pcDataCon word8DataConName [] [wordPrimTy] word8TyCon floatTy :: Type floatTy = mkTyConTy floatTyCon floatTyCon :: TyCon floatTyCon = pcTyCon floatTyConName (Just (CType NoSourceText Nothing (NoSourceText, fsLit "HsFloat"))) [] [floatDataCon] floatDataCon :: DataCon floatDataCon = pcDataCon floatDataConName [] [floatPrimTy] floatTyCon doubleTy :: Type doubleTy = mkTyConTy doubleTyCon doubleTyCon :: TyCon doubleTyCon = pcTyCon doubleTyConName (Just (CType NoSourceText Nothing (NoSourceText,fsLit "HsDouble"))) [] [doubleDataCon] doubleDataCon :: DataCon doubleDataCon = pcDataCon doubleDataConName [] [doublePrimTy] doubleTyCon {- ************************************************************************ * * The Bool type * * ************************************************************************ An ordinary enumeration type, but deeply wired in. There are no magical operations on @Bool@ (just the regular Prelude code). {\em BEGIN IDLE SPECULATION BY SIMON} This is not the only way to encode @Bool@. A more obvious coding makes @Bool@ just a boxed up version of @Bool#@, like this: \begin{verbatim} type Bool# = Int# data Bool = MkBool Bool# \end{verbatim} Unfortunately, this doesn't correspond to what the Report says @Bool@ looks like! Furthermore, we get slightly less efficient code (I think) with this coding. @gtInt@ would look like this: \begin{verbatim} gtInt :: Int -> Int -> Bool gtInt x y = case x of I# x# -> case y of I# y# -> case (gtIntPrim x# y#) of b# -> MkBool b# \end{verbatim} Notice that the result of the @gtIntPrim@ comparison has to be turned into an integer (here called @b#@), and returned in a @MkBool@ box. The @if@ expression would compile to this: \begin{verbatim} case (gtInt x y) of MkBool b# -> case b# of { 1# -> e1; 0# -> e2 } \end{verbatim} I think this code is a little less efficient than the previous code, but I'm not certain. At all events, corresponding with the Report is important. The interesting thing is that the language is expressive enough to describe more than one alternative; and that a type doesn't necessarily need to be a straightforwardly boxed version of its primitive counterpart. {\em END IDLE SPECULATION BY SIMON} -} boolTy :: Type boolTy = mkTyConTy boolTyCon boolTyCon :: TyCon boolTyCon = pcTyCon boolTyConName (Just (CType NoSourceText Nothing (NoSourceText, fsLit "HsBool"))) [] [falseDataCon, trueDataCon] falseDataCon, trueDataCon :: DataCon falseDataCon = pcDataCon falseDataConName [] [] boolTyCon trueDataCon = pcDataCon trueDataConName [] [] boolTyCon falseDataConId, trueDataConId :: Id falseDataConId = dataConWorkId falseDataCon trueDataConId = dataConWorkId trueDataCon orderingTyCon :: TyCon orderingTyCon = pcTyCon orderingTyConName Nothing [] [ltDataCon, eqDataCon, gtDataCon] ltDataCon, eqDataCon, gtDataCon :: DataCon ltDataCon = pcDataCon ltDataConName [] [] orderingTyCon eqDataCon = pcDataCon eqDataConName [] [] orderingTyCon gtDataCon = pcDataCon gtDataConName [] [] orderingTyCon ltDataConId, eqDataConId, gtDataConId :: Id ltDataConId = dataConWorkId ltDataCon eqDataConId = dataConWorkId eqDataCon gtDataConId = dataConWorkId gtDataCon {- ************************************************************************ * * The List type Special syntax, deeply wired in, but otherwise an ordinary algebraic data type * * ************************************************************************ data [] a = [] | a : (List a) -} mkListTy :: Type -> Type mkListTy ty = mkTyConApp listTyCon [ty] listTyCon :: TyCon listTyCon = buildAlgTyCon listTyConName alpha_tyvar [Representational] Nothing [] (mkDataTyConRhs [nilDataCon, consDataCon]) False (VanillaAlgTyCon $ mkPrelTyConRepName listTyConName) nilDataCon :: DataCon nilDataCon = pcDataCon nilDataConName alpha_tyvar [] listTyCon consDataCon :: DataCon consDataCon = pcDataConWithFixity True {- Declared infix -} consDataConName alpha_tyvar [] alpha_tyvar [alphaTy, mkTyConApp listTyCon alpha_ty] listTyCon -- Interesting: polymorphic recursion would help here. -- We can't use (mkListTy alphaTy) in the defn of consDataCon, else mkListTy -- gets the over-specific type (Type -> Type) -- Wired-in type Maybe maybeTyCon :: TyCon maybeTyCon = pcTyCon maybeTyConName Nothing alpha_tyvar [nothingDataCon, justDataCon] nothingDataCon :: DataCon nothingDataCon = pcDataCon nothingDataConName alpha_tyvar [] maybeTyCon justDataCon :: DataCon justDataCon = pcDataCon justDataConName alpha_tyvar [alphaTy] maybeTyCon {- ** ********************************************************************* * * The tuple types * * ************************************************************************ The tuple types are definitely magic, because they form an infinite family. \begin{itemize} \item They have a special family of type constructors, of type @TyCon@ These contain the tycon arity, but don't require a Unique. \item They have a special family of constructors, of type @Id@. Again these contain their arity but don't need a Unique. \item There should be a magic way of generating the info tables and entry code for all tuples. But at the moment we just compile a Haskell source file\srcloc{lib/prelude/...} containing declarations like: \begin{verbatim} data Tuple0 = Tup0 data Tuple2 a b = Tup2 a b data Tuple3 a b c = Tup3 a b c data Tuple4 a b c d = Tup4 a b c d ... \end{verbatim} The print-names associated with the magic @Id@s for tuple constructors ``just happen'' to be the same as those generated by these declarations. \item The instance environment should have a magic way to know that each tuple type is an instances of classes @Eq@, @Ix@, @Ord@ and so on. \ToDo{Not implemented yet.} \item There should also be a way to generate the appropriate code for each of these instances, but (like the info tables and entry code) it is done by enumeration\srcloc{lib/prelude/InTup?.hs}. \end{itemize} -} -- | Make a tuple type. The list of types should /not/ include any -- RuntimeRep specifications. mkTupleTy :: Boxity -> [Type] -> Type -- Special case for *boxed* 1-tuples, which are represented by the type itself mkTupleTy Boxed [ty] = ty mkTupleTy Boxed tys = mkTyConApp (tupleTyCon Boxed (length tys)) tys mkTupleTy Unboxed tys = mkTyConApp (tupleTyCon Unboxed (length tys)) (map getRuntimeRep tys ++ tys) -- | Build the type of a small tuple that holds the specified type of thing mkBoxedTupleTy :: [Type] -> Type mkBoxedTupleTy tys = mkTupleTy Boxed tys unitTy :: Type unitTy = mkTupleTy Boxed [] {- ********************************************************************* * * The sum types * * ************************************************************************ -} mkSumTy :: [Type] -> Type mkSumTy tys = mkTyConApp (sumTyCon (length tys)) (map getRuntimeRep tys ++ tys) -- Promoted Booleans promotedFalseDataCon, promotedTrueDataCon :: TyCon promotedTrueDataCon = promoteDataCon trueDataCon promotedFalseDataCon = promoteDataCon falseDataCon -- Promoted Maybe promotedNothingDataCon, promotedJustDataCon :: TyCon promotedNothingDataCon = promoteDataCon nothingDataCon promotedJustDataCon = promoteDataCon justDataCon -- Promoted Ordering promotedLTDataCon , promotedEQDataCon , promotedGTDataCon :: TyCon promotedLTDataCon = promoteDataCon ltDataCon promotedEQDataCon = promoteDataCon eqDataCon promotedGTDataCon = promoteDataCon gtDataCon -- Promoted List promotedConsDataCon, promotedNilDataCon :: TyCon promotedConsDataCon = promoteDataCon consDataCon promotedNilDataCon = promoteDataCon nilDataCon -- | Make a *promoted* list. mkPromotedListTy :: Kind -- ^ of the elements of the list -> [Type] -- ^ elements -> Type mkPromotedListTy k tys = foldr cons nil tys where cons :: Type -- element -> Type -- list -> Type cons elt list = mkTyConApp promotedConsDataCon [k, elt, list] nil :: Type nil = mkTyConApp promotedNilDataCon [k] -- | Extract the elements of a promoted list. Panics if the type is not a -- promoted list extractPromotedList :: Type -- ^ The promoted list -> [Type] extractPromotedList tys = go tys where go list_ty | Just (tc, [_k, t, ts]) <- splitTyConApp_maybe list_ty = ASSERT( tc `hasKey` consDataConKey ) t : go ts | Just (tc, [_k]) <- splitTyConApp_maybe list_ty = ASSERT( tc `hasKey` nilDataConKey ) [] | otherwise = pprPanic "extractPromotedList" (ppr tys)