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Diffstat (limited to 'compiler/prelude/TysWiredIn.lhs')
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diff --git a/compiler/prelude/TysWiredIn.lhs b/compiler/prelude/TysWiredIn.lhs new file mode 100644 index 0000000000..ceb4df550a --- /dev/null +++ b/compiler/prelude/TysWiredIn.lhs @@ -0,0 +1,549 @@ +% +% (c) The GRASP Project, Glasgow University, 1994-1998 +% +\section[TysWiredIn]{Wired-in knowledge about {\em non-primitive} types} + +This module is about types that can be defined in Haskell, but which +must be wired into the compiler nonetheless. + +This module tracks the ``state interface'' document, ``GHC prelude: +types and operations.'' + +\begin{code} +module TysWiredIn ( + wiredInTyCons, + + boolTy, boolTyCon, boolTyCon_RDR, boolTyConName, + trueDataCon, trueDataConId, true_RDR, + falseDataCon, falseDataConId, false_RDR, + + charTyCon, charDataCon, charTyCon_RDR, + charTy, stringTy, charTyConName, + + + doubleTyCon, doubleDataCon, doubleTy, doubleTyConName, + + floatTyCon, floatDataCon, floatTy, floatTyConName, + + intTyCon, intDataCon, intTyCon_RDR, intDataCon_RDR, intTyConName, + intTy, + + listTyCon, nilDataCon, consDataCon, + listTyCon_RDR, consDataCon_RDR, listTyConName, + mkListTy, + + -- tuples + mkTupleTy, + tupleTyCon, tupleCon, + unitTyCon, unitDataCon, unitDataConId, pairTyCon, + unboxedSingletonTyCon, unboxedSingletonDataCon, + unboxedPairTyCon, unboxedPairDataCon, + + unitTy, + voidTy, + + -- parallel arrays + mkPArrTy, + parrTyCon, parrFakeCon, isPArrTyCon, isPArrFakeCon, + parrTyCon_RDR, parrTyConName + ) where + +#include "HsVersions.h" + +import {-# SOURCE #-} MkId( mkDataConIds ) + +-- friends: +import PrelNames +import TysPrim + +-- others: +import Constants ( mAX_TUPLE_SIZE ) +import Module ( Module ) +import RdrName ( nameRdrName ) +import Name ( Name, BuiltInSyntax(..), nameUnique, nameOccName, + nameModule, mkWiredInName ) +import OccName ( mkOccNameFS, tcName, dataName, mkTupleOcc, + mkDataConWorkerOcc ) +import DataCon ( DataCon, mkDataCon, dataConWorkId, dataConSourceArity ) +import Var ( TyVar, tyVarKind ) +import TyCon ( TyCon, AlgTyConRhs(DataTyCon), tyConDataCons, + mkTupleTyCon, mkAlgTyCon, tyConName ) + +import BasicTypes ( Arity, RecFlag(..), Boxity(..), isBoxed, + StrictnessMark(..) ) + +import Type ( Type, mkTyConTy, mkTyConApp, mkTyVarTy, mkTyVarTys, + TyThing(..) ) +import Kind ( mkArrowKinds, liftedTypeKind, ubxTupleKind ) +import Unique ( incrUnique, mkTupleTyConUnique, + mkTupleDataConUnique, mkPArrDataConUnique ) +import Array +import FastString +import Outputable + +alpha_tyvar = [alphaTyVar] +alpha_ty = [alphaTy] +\end{code} + + +%************************************************************************ +%* * +\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 + +\begin{code} +wiredInTyCons :: [TyCon] -- Excludes tuples +wiredInTyCons = [ unitTyCon -- Not treated like other tuples, because + -- it's defined in GHC.Base, and there's only + -- one of it. We put it in wiredInTyCons so + -- that it'll pre-populate the name cache, so + -- the special case in lookupOrigNameCache + -- doesn't need to look out for it + , boolTyCon + , charTyCon + , doubleTyCon + , floatTyCon + , intTyCon + , listTyCon + , parrTyCon + ] +\end{code} + +\begin{code} +mkWiredInTyConName :: BuiltInSyntax -> Module -> FastString -> Unique -> TyCon -> Name +mkWiredInTyConName built_in mod fs uniq tycon + = mkWiredInName mod (mkOccNameFS tcName fs) uniq + Nothing -- No parent object + (ATyCon tycon) -- Relevant TyCon + built_in + +mkWiredInDataConName :: BuiltInSyntax -> Module -> FastString -> Unique -> DataCon -> Name -> Name +mkWiredInDataConName built_in mod fs uniq datacon parent + = mkWiredInName mod (mkOccNameFS dataName fs) uniq + (Just parent) -- Name of parent TyCon + (ADataCon datacon) -- Relevant DataCon + built_in + +charTyConName = mkWiredInTyConName UserSyntax pREL_BASE FSLIT("Char") charTyConKey charTyCon +charDataConName = mkWiredInDataConName UserSyntax pREL_BASE FSLIT("C#") charDataConKey charDataCon charTyConName +intTyConName = mkWiredInTyConName UserSyntax pREL_BASE FSLIT("Int") intTyConKey intTyCon +intDataConName = mkWiredInDataConName UserSyntax pREL_BASE FSLIT("I#") intDataConKey intDataCon intTyConName + +boolTyConName = mkWiredInTyConName UserSyntax pREL_BASE FSLIT("Bool") boolTyConKey boolTyCon +falseDataConName = mkWiredInDataConName UserSyntax pREL_BASE FSLIT("False") falseDataConKey falseDataCon boolTyConName +trueDataConName = mkWiredInDataConName UserSyntax pREL_BASE FSLIT("True") trueDataConKey trueDataCon boolTyConName +listTyConName = mkWiredInTyConName BuiltInSyntax pREL_BASE FSLIT("[]") listTyConKey listTyCon +nilDataConName = mkWiredInDataConName BuiltInSyntax pREL_BASE FSLIT("[]") nilDataConKey nilDataCon listTyConName +consDataConName = mkWiredInDataConName BuiltInSyntax pREL_BASE FSLIT(":") consDataConKey consDataCon listTyConName + +floatTyConName = mkWiredInTyConName UserSyntax pREL_FLOAT FSLIT("Float") floatTyConKey floatTyCon +floatDataConName = mkWiredInDataConName UserSyntax pREL_FLOAT FSLIT("F#") floatDataConKey floatDataCon floatTyConName +doubleTyConName = mkWiredInTyConName UserSyntax pREL_FLOAT FSLIT("Double") doubleTyConKey doubleTyCon +doubleDataConName = mkWiredInDataConName UserSyntax pREL_FLOAT FSLIT("D#") doubleDataConKey doubleDataCon doubleTyConName + +parrTyConName = mkWiredInTyConName BuiltInSyntax pREL_PARR FSLIT("[::]") parrTyConKey parrTyCon +parrDataConName = mkWiredInDataConName UserSyntax pREL_PARR FSLIT("PArr") parrDataConKey parrDataCon parrTyConName + +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 +parrTyCon_RDR = nameRdrName parrTyConName +\end{code} + + +%************************************************************************ +%* * +\subsection{mkWiredInTyCon} +%* * +%************************************************************************ + +\begin{code} +pcNonRecDataTyCon = pcTyCon False NonRecursive +pcRecDataTyCon = pcTyCon False Recursive + +pcTyCon is_enum is_rec name tyvars argvrcs cons + = tycon + where + tycon = mkAlgTyCon name + (mkArrowKinds (map tyVarKind tyvars) liftedTypeKind) + tyvars + argvrcs + [] -- No stupid theta + (DataTyCon cons is_enum) + [] -- No record selectors + is_rec + True -- All the wired-in tycons have generics + +pcDataCon :: Name -> [TyVar] -> [Type] -> TyCon -> DataCon +pcDataCon = pcDataConWithFixity False + +pcDataConWithFixity :: Bool -> Name -> [TyVar] -> [Type] -> TyCon -> DataCon +-- The Name should be in the DataName name space; it's the name +-- of the DataCon itself. +-- +-- The unique is the first of two free uniques; +-- the first is used for the datacon itself, +-- the second is used for the "worker name" + +pcDataConWithFixity declared_infix dc_name tyvars arg_tys tycon + = data_con + where + data_con = mkDataCon dc_name declared_infix True {- Vanilla -} + (map (const NotMarkedStrict) arg_tys) + [{- No labelled fields -}] + tyvars [] [] arg_tys tycon (mkTyVarTys tyvars) + (mkDataConIds bogus_wrap_name wrk_name data_con) + + + mod = nameModule dc_name + wrk_occ = mkDataConWorkerOcc (nameOccName dc_name) + wrk_key = incrUnique (nameUnique dc_name) + wrk_name = mkWiredInName mod wrk_occ wrk_key + (Just (tyConName tycon)) + (AnId (dataConWorkId data_con)) UserSyntax + bogus_wrap_name = pprPanic "Wired-in data wrapper id" (ppr dc_name) + -- Wired-in types are too simple to need wrappers +\end{code} + + +%************************************************************************ +%* * +\subsection[TysWiredIn-tuples]{The tuple types} +%* * +%************************************************************************ + +\begin{code} +tupleTyCon :: Boxity -> Arity -> TyCon +tupleTyCon boxity i | i > mAX_TUPLE_SIZE = fst (mk_tuple boxity i) -- Build one specially +tupleTyCon Boxed i = fst (boxedTupleArr ! i) +tupleTyCon Unboxed i = fst (unboxedTupleArr ! i) + +tupleCon :: Boxity -> Arity -> DataCon +tupleCon boxity i | i > mAX_TUPLE_SIZE = snd (mk_tuple boxity i) -- Build one specially +tupleCon Boxed i = snd (boxedTupleArr ! i) +tupleCon 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]] + +mk_tuple :: Boxity -> Int -> (TyCon,DataCon) +mk_tuple boxity arity = (tycon, tuple_con) + where + tycon = mkTupleTyCon tc_name tc_kind arity tyvars tuple_con boxity gen_info + mod = mkTupleModule boxity arity + tc_name = mkWiredInName mod (mkTupleOcc tcName boxity arity) tc_uniq + Nothing (ATyCon tycon) BuiltInSyntax + tc_kind = mkArrowKinds (map tyVarKind tyvars) res_kind + res_kind | isBoxed boxity = liftedTypeKind + | otherwise = ubxTupleKind + + tyvars | isBoxed boxity = take arity alphaTyVars + | otherwise = take arity openAlphaTyVars + + tuple_con = pcDataCon dc_name tyvars tyvar_tys tycon + tyvar_tys = mkTyVarTys tyvars + dc_name = mkWiredInName mod (mkTupleOcc dataName boxity arity) dc_uniq + (Just tc_name) (ADataCon tuple_con) BuiltInSyntax + tc_uniq = mkTupleTyConUnique boxity arity + dc_uniq = mkTupleDataConUnique boxity arity + gen_info = True -- Tuples all have generics.. + -- hmm: that's a *lot* of code + +unitTyCon = tupleTyCon Boxed 0 +unitDataCon = head (tyConDataCons unitTyCon) +unitDataConId = dataConWorkId unitDataCon + +pairTyCon = tupleTyCon Boxed 2 + +unboxedSingletonTyCon = tupleTyCon Unboxed 1 +unboxedSingletonDataCon = tupleCon Unboxed 1 + +unboxedPairTyCon = tupleTyCon Unboxed 2 +unboxedPairDataCon = tupleCon Unboxed 2 +\end{code} + +%************************************************************************ +%* * +\subsection[TysWiredIn-boxed-prim]{The ``boxed primitive'' types (@Char@, @Int@, etc)} +%* * +%************************************************************************ + +\begin{code} +-- The Void type is represented as a data type with no constructors +-- It's a built in type (i.e. there's no way to define it in Haskell; +-- the nearest would be +-- +-- data Void = -- No constructors! +-- +-- ) It's lifted; there is only one value of this +-- type, namely "void", whose semantics is just bottom. +-- +-- Haskell 98 drops the definition of a Void type, so we just 'simulate' +-- voidTy using (). +voidTy = unitTy +\end{code} + + +\begin{code} +charTy = mkTyConTy charTyCon + +charTyCon = pcNonRecDataTyCon charTyConName [] [] [charDataCon] +charDataCon = pcDataCon charDataConName [] [charPrimTy] charTyCon + +stringTy = mkListTy charTy -- convenience only +\end{code} + +\begin{code} +intTy = mkTyConTy intTyCon + +intTyCon = pcNonRecDataTyCon intTyConName [] [] [intDataCon] +intDataCon = pcDataCon intDataConName [] [intPrimTy] intTyCon +\end{code} + +\begin{code} +floatTy = mkTyConTy floatTyCon + +floatTyCon = pcNonRecDataTyCon floatTyConName [] [] [floatDataCon] +floatDataCon = pcDataCon floatDataConName [] [floatPrimTy] floatTyCon +\end{code} + +\begin{code} +doubleTy = mkTyConTy doubleTyCon + +doubleTyCon = pcNonRecDataTyCon doubleTyConName [] [] [doubleDataCon] +doubleDataCon = pcDataCon doubleDataConName [] [doublePrimTy] doubleTyCon +\end{code} + + +%************************************************************************ +%* * +\subsection[TysWiredIn-Bool]{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} + +\begin{code} +boolTy = mkTyConTy boolTyCon + +boolTyCon = pcTyCon True NonRecursive boolTyConName + [] [] [falseDataCon, trueDataCon] + +falseDataCon = pcDataCon falseDataConName [] [] boolTyCon +trueDataCon = pcDataCon trueDataConName [] [] boolTyCon + +falseDataConId = dataConWorkId falseDataCon +trueDataConId = dataConWorkId trueDataCon +\end{code} + +%************************************************************************ +%* * +\subsection[TysWiredIn-List]{The @List@ type (incl ``build'' magic)} +%* * +%************************************************************************ + +Special syntax, deeply wired in, but otherwise an ordinary algebraic +data types: +\begin{verbatim} +data [] a = [] | a : (List a) +data () = () +data (,) a b = (,,) a b +... +\end{verbatim} + +\begin{code} +mkListTy :: Type -> Type +mkListTy ty = mkTyConApp listTyCon [ty] + +listTyCon = pcRecDataTyCon listTyConName + alpha_tyvar [(True,False)] [nilDataCon, consDataCon] + +nilDataCon = pcDataCon nilDataConName alpha_tyvar [] listTyCon +consDataCon = pcDataConWithFixity True {- Declared infix -} + consDataConName + 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) +\end{code} + +%************************************************************************ +%* * +\subsection[TysWiredIn-Tuples]{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} + +\begin{code} +mkTupleTy :: Boxity -> Int -> [Type] -> Type +mkTupleTy boxity arity tys = mkTyConApp (tupleTyCon boxity arity) tys + +unitTy = mkTupleTy Boxed 0 [] +\end{code} + +%************************************************************************ +%* * +\subsection[TysWiredIn-PArr]{The @[::]@ type} +%* * +%************************************************************************ + +Special syntax for parallel arrays needs some wired in definitions. + +\begin{code} +-- construct a type representing the application of the parallel array +-- constructor +-- +mkPArrTy :: Type -> Type +mkPArrTy ty = mkTyConApp parrTyCon [ty] + +-- represents the type constructor of parallel arrays +-- +-- * this must match the definition in `PrelPArr' +-- +-- NB: Although the constructor is given here, it will not be accessible in +-- user code as it is not in the environment of any compiled module except +-- `PrelPArr'. +-- +parrTyCon :: TyCon +parrTyCon = pcNonRecDataTyCon parrTyConName alpha_tyvar [(True, False)] [parrDataCon] + +parrDataCon :: DataCon +parrDataCon = pcDataCon + parrDataConName + alpha_tyvar -- forall'ed type variables + [intPrimTy, -- 1st argument: Int# + mkTyConApp -- 2nd argument: Array# a + arrayPrimTyCon + alpha_ty] + parrTyCon + +-- check whether a type constructor is the constructor for parallel arrays +-- +isPArrTyCon :: TyCon -> Bool +isPArrTyCon tc = tyConName tc == parrTyConName + +-- fake array constructors +-- +-- * these constructors are never really used to represent array values; +-- however, they are very convenient during desugaring (and, in particular, +-- in the pattern matching compiler) to treat array pattern just like +-- yet another constructor pattern +-- +parrFakeCon :: Arity -> DataCon +parrFakeCon i | i > mAX_TUPLE_SIZE = mkPArrFakeCon i -- build one specially +parrFakeCon i = parrFakeConArr!i + +-- pre-defined set of constructors +-- +parrFakeConArr :: Array Int DataCon +parrFakeConArr = array (0, mAX_TUPLE_SIZE) [(i, mkPArrFakeCon i) + | i <- [0..mAX_TUPLE_SIZE]] + +-- build a fake parallel array constructor for the given arity +-- +mkPArrFakeCon :: Int -> DataCon +mkPArrFakeCon arity = data_con + where + data_con = pcDataCon name [tyvar] tyvarTys parrTyCon + tyvar = head alphaTyVars + tyvarTys = replicate arity $ mkTyVarTy tyvar + nameStr = mkFastString ("MkPArr" ++ show arity) + name = mkWiredInName pREL_PARR (mkOccNameFS dataName nameStr) uniq + Nothing (ADataCon data_con) UserSyntax + uniq = mkPArrDataConUnique arity + +-- checks whether a data constructor is a fake constructor for parallel arrays +-- +isPArrFakeCon :: DataCon -> Bool +isPArrFakeCon dcon = dcon == parrFakeCon (dataConSourceArity dcon) +\end{code} + |