X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Fiface%2FBuildTyCl.lhs;h=333d8084ce4a301144cadb1ddcde85b41ef3c47c;hp=5f23fd5fb4e5b8b8aae7533be3d0d9639de25806;hb=6777144f7522d8db5935737e12fa451ca3211e6d;hpb=909d2dd885f5eebaf7c12cf15d5ac153d646566e diff --git a/compiler/iface/BuildTyCl.lhs b/compiler/iface/BuildTyCl.lhs index 5f23fd5..333d808 100644 --- a/compiler/iface/BuildTyCl.lhs +++ b/compiler/iface/BuildTyCl.lhs @@ -1,4 +1,5 @@ % +% (c) The University of Glasgow 2006 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % @@ -6,61 +7,57 @@ module BuildTyCl ( buildSynTyCon, buildAlgTyCon, buildDataCon, buildClass, - mkAbstractTyConRhs, mkOpenDataTyConRhs, mkOpenNewTyConRhs, + mkAbstractTyConRhs, mkOpenDataTyConRhs, mkNewTyConRhs, mkDataTyConRhs ) where #include "HsVersions.h" -import IfaceEnv ( newImplicitBinder ) +import IfaceEnv import TcRnMonad -import DataCon ( DataCon, isNullarySrcDataCon, dataConUnivTyVars, - mkDataCon, dataConFieldLabels, dataConInstOrigArgTys, - dataConTyCon ) -import Var ( tyVarKind, TyVar, Id ) -import VarSet ( isEmptyVarSet, intersectVarSet, elemVarSet ) -import TysWiredIn ( unitTy ) -import BasicTypes ( RecFlag, StrictnessMark(..) ) -import Name ( Name ) -import OccName ( mkDataConWrapperOcc, mkDataConWorkerOcc, - mkClassTyConOcc, mkClassDataConOcc, - mkSuperDictSelOcc, mkNewTyCoOcc, mkInstTyTcOcc, - mkInstTyCoOcc ) -import MkId ( mkDataConIds, mkRecordSelId, mkDictSelId ) -import Class ( mkClass, Class( classTyCon), FunDep, DefMeth(..) ) -import TyCon ( mkSynTyCon, mkAlgTyCon, visibleDataCons, - tyConStupidTheta, tyConDataCons, isNewTyCon, - mkClassTyCon, TyCon( tyConTyVars ), - isRecursiveTyCon, tyConArity, AlgTyConRhs(..), - SynTyConRhs(..), newTyConRhs, AlgTyConParent(..) ) -import Type ( mkArrowKinds, liftedTypeKind, typeKind, - tyVarsOfType, tyVarsOfTypes, tyVarsOfPred, - splitTyConApp_maybe, splitAppTy_maybe, - getTyVar_maybe, - mkPredTys, mkTyVarTys, ThetaType, Type, Kind, - TyThing(..), - substTyWith, zipTopTvSubst, substTheta, mkForAllTys, - mkTyConApp, mkTyVarTy ) -import Coercion ( mkNewTypeCoercion, mkDataInstCoercion ) -import Outputable -import List ( nub ) - +import DataCon +import Var +import VarSet +import TysWiredIn +import BasicTypes +import Name +import OccName +import MkId +import Class +import TyCon +import Type +import Coercion + +import Data.List \end{code} \begin{code} ------------------------------------------------------ -buildSynTyCon :: Name -> [TyVar] -> SynTyConRhs -> TyCon -buildSynTyCon name tvs rhs@(OpenSynTyCon rhs_ki) - = mkSynTyCon name kind tvs rhs - where - kind = mkArrowKinds (map tyVarKind tvs) rhs_ki -buildSynTyCon name tvs rhs@(SynonymTyCon rhs_ty) - = mkSynTyCon name kind tvs rhs - where - kind = mkArrowKinds (map tyVarKind tvs) (typeKind rhs_ty) - +buildSynTyCon :: Name -> [TyVar] + -> SynTyConRhs + -> Maybe (TyCon, [Type]) -- family instance if applicable + -> TcRnIf m n TyCon + +buildSynTyCon tc_name tvs rhs@(OpenSynTyCon rhs_ki _) _ + = let + kind = mkArrowKinds (map tyVarKind tvs) rhs_ki + in + return $ mkSynTyCon tc_name kind tvs rhs NoParentTyCon + +buildSynTyCon tc_name tvs rhs@(SynonymTyCon rhs_ty) mb_family + = do { -- We need to tie a knot as the coercion of a data instance depends + -- on the instance representation tycon and vice versa. + ; tycon <- fixM (\ tycon_rec -> do + { parent <- mkParentInfo mb_family tc_name tvs tycon_rec + ; let { tycon = mkSynTyCon tc_name kind tvs rhs parent + ; kind = mkArrowKinds (map tyVarKind tvs) (typeKind rhs_ty) + } + ; return tycon + }) + ; return tycon + } ------------------------------------------------------ buildAlgTyCon :: Name -> [TyVar] @@ -69,8 +66,7 @@ buildAlgTyCon :: Name -> [TyVar] -> RecFlag -> Bool -- True <=> want generics functions -> Bool -- True <=> was declared in GADT syntax - -> Maybe (TyCon, [Type]) -- Just (family, tys) - -- <=> instance of `family' at `tys' + -> Maybe (TyCon, [Type]) -- family instance if applicable -> TcRnIf m n TyCon buildAlgTyCon tc_name tvs stupid_theta rhs is_rec want_generics gadt_syn @@ -78,8 +74,8 @@ buildAlgTyCon tc_name tvs stupid_theta rhs is_rec want_generics gadt_syn = do { -- We need to tie a knot as the coercion of a data instance depends -- on the instance representation tycon and vice versa. ; tycon <- fixM (\ tycon_rec -> do - { (final_name, parent) <- maybeComputeFamilyInfo mb_family tycon_rec - ; let { tycon = mkAlgTyCon final_name kind tvs stupid_theta rhs + { parent <- mkParentInfo mb_family tc_name tvs tycon_rec + ; let { tycon = mkAlgTyCon tc_name kind tvs stupid_theta rhs fields parent is_rec want_generics gadt_syn ; kind = mkArrowKinds (map tyVarKind tvs) liftedTypeKind ; fields = mkTyConSelIds tycon rhs @@ -88,46 +84,38 @@ buildAlgTyCon tc_name tvs stupid_theta rhs is_rec want_generics gadt_syn }) ; return tycon } - where - -- If a family tycon with instance types is given, the current tycon is an - -- instance of that family and we have to perform three extra tasks: - -- - -- (1) The instance tycon (representing the family at a particular type - -- instance) need to get a new, derived name - we may not reuse the - -- family name. - -- (2) Create a coercion that identifies the family instance type and the - -- representation type from Step (1); ie, it is of the form - -- `Co tvs :: F ts :=: R tvs', where `Co' is the name of the coercion, - -- `F' the family tycon and `R' the (derived) representation tycon. - -- (3) Produce a `AlgTyConParent' value containing the parent and coercion - -- information. - -- - maybeComputeFamilyInfo Nothing rep_tycon = - return (tc_name, NoParentTyCon) - maybeComputeFamilyInfo (Just (family, instTys)) rep_tycon = - do { -- (1) New, derived name for the instance tycon - ; uniq <- newUnique - ; final_name <- newImplicitBinder tc_name (mkInstTyTcOcc uniq) - - -- (2) Create the coercion. - ; co_tycon_name <- newImplicitBinder tc_name (mkInstTyCoOcc uniq) - ; let co_tycon = mkDataInstCoercion co_tycon_name tvs - family instTys rep_tycon - - -- (3) Produce parent information. - ; return (final_name, FamilyTyCon family instTys co_tycon) - } - +-- If a family tycon with instance types is given, the current tycon is an +-- instance of that family and we need to +-- +-- (1) create a coercion that identifies the family instance type and the +-- representation type from Step (1); ie, it is of the form +-- `Co tvs :: F ts :=: R tvs', where `Co' is the name of the coercion, +-- `F' the family tycon and `R' the (derived) representation tycon, +-- and +-- (2) produce a `TyConParent' value containing the parent and coercion +-- information. +-- +mkParentInfo :: Maybe (TyCon, [Type]) + -> Name -> [TyVar] + -> TyCon + -> TcRnIf m n TyConParent +mkParentInfo Nothing _ _ _ = + return NoParentTyCon +mkParentInfo (Just (family, instTys)) tc_name tvs rep_tycon = + do { -- Create the coercion + ; co_tycon_name <- newImplicitBinder tc_name mkInstTyCoOcc + ; let co_tycon = mkFamInstCoercion co_tycon_name tvs + family instTys rep_tycon + ; return $ FamilyTyCon family instTys co_tycon + } + ------------------------------------------------------ mkAbstractTyConRhs :: AlgTyConRhs mkAbstractTyConRhs = AbstractTyCon mkOpenDataTyConRhs :: AlgTyConRhs -mkOpenDataTyConRhs = OpenDataTyCon - -mkOpenNewTyConRhs :: AlgTyConRhs -mkOpenNewTyConRhs = OpenNewTyCon +mkOpenDataTyConRhs = OpenTyCon Nothing mkDataTyConRhs :: [DataCon] -> AlgTyConRhs mkDataTyConRhs cons @@ -139,21 +127,20 @@ mkNewTyConRhs :: Name -> TyCon -> DataCon -> TcRnIf m n AlgTyConRhs -- because the latter is part of a knot, whereas the former is not. mkNewTyConRhs tycon_name tycon con = do { co_tycon_name <- newImplicitBinder tycon_name mkNewTyCoOcc - ; let co_tycon = mkNewTypeCoercion co_tycon_name tycon tvs rhs_ty - cocon_maybe - | all_coercions || isRecursiveTyCon tycon - = Just co_tycon - | otherwise - = Nothing - ; return (NewTyCon { data_con = con, - nt_co = cocon_maybe, + ; let co_tycon = mkNewTypeCoercion co_tycon_name tycon etad_tvs etad_rhs + cocon_maybe | all_coercions || isRecursiveTyCon tycon + = Just co_tycon + | otherwise + = Nothing + ; return (NewTyCon { data_con = con, + nt_rhs = rhs_ty, + nt_etad_rhs = (etad_tvs, etad_rhs), + nt_co = cocon_maybe, -- Coreview looks through newtypes with a Nothing -- for nt_co, or uses explicit coercions otherwise - nt_rhs = rhs_ty, - nt_etad_rhs = eta_reduce tvs rhs_ty, nt_rep = mkNewTyConRep tycon rhs_ty }) } where - -- if all_coercions is True then we use coercions for all newtypes + -- If all_coercions is True then we use coercions for all newtypes -- otherwise we use coercions for recursive newtypes and look through -- non-recursive newtypes all_coercions = True @@ -162,18 +149,22 @@ mkNewTyConRhs tycon_name tycon con -- Instantiate the data con with the -- type variables from the tycon - eta_reduce [] ty = ([], ty) - eta_reduce (a:as) ty | null as', - Just (fun, arg) <- splitAppTy_maybe ty', + etad_tvs :: [TyVar] -- Matched lazily, so that mkNewTypeCoercion can + etad_rhs :: Type -- return a TyCon without pulling on rhs_ty + -- See Note [Tricky iface loop] in LoadIface + (etad_tvs, etad_rhs) = eta_reduce (reverse tvs) rhs_ty + + eta_reduce :: [TyVar] -- Reversed + -> Type -- Rhs type + -> ([TyVar], Type) -- Eta-reduced version (tyvars in normal order) + eta_reduce (a:as) ty | Just (fun, arg) <- splitAppTy_maybe ty, Just tv <- getTyVar_maybe arg, tv == a, not (a `elemVarSet` tyVarsOfType fun) - = ([], fun) -- Successful eta reduction - | otherwise - = (a:as', ty') - where - (as', ty') = eta_reduce as ty + = eta_reduce as fun + eta_reduce tvs ty = (reverse tvs, ty) + mkNewTyConRep :: TyCon -- The original type constructor -> Type -- The arg type of its constructor -> Type -- Chosen representation type @@ -323,7 +314,7 @@ buildClass class_name tvs sc_theta fds ats sig_stuff tc_isrec ; let { clas_kind = mkArrowKinds (map tyVarKind tvs) liftedTypeKind ; tycon = mkClassTyCon tycon_name clas_kind tvs - rhs rec_clas tc_isrec + rhs rec_clas tc_isrec -- A class can be recursive, and in the case of newtypes -- this matters. For example -- class C a where { op :: C b => a -> b -> Int }