X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2Ftypes%2FTyCon.lhs;h=d7347a84b68365630421ecccb5ee52c3dcaf4dfb;hp=51bc1f1d0ba7b466d5a891b5813d142bb79948ab;hb=8c2fd74094dc533bf3256158325e3f091e57e5d2;hpb=f37e239fb5e81fc493e0ea1af98178bf1f7ceaba diff --git a/compiler/types/TyCon.lhs b/compiler/types/TyCon.lhs index 51bc1f1..d7347a8 100644 --- a/compiler/types/TyCon.lhs +++ b/compiler/types/TyCon.lhs @@ -1,7 +1,9 @@ % +% (c) The University of Glasgow 2006 % (c) The GRASP/AQUA Project, Glasgow University, 1992-1998 % -\section[TyCon]{The @TyCon@ datatype} + +The @TyCon@ datatype \begin{code} module TyCon( @@ -9,19 +11,25 @@ module TyCon( PrimRep(..), tyConPrimRep, + primRepSizeW, - AlgTyConRhs(..), visibleDataCons, AlgTyConParent(..), + AlgTyConRhs(..), visibleDataCons, + TyConParent(..), SynTyConRhs(..), isFunTyCon, isUnLiftedTyCon, isProductTyCon, - isAlgTyCon, isDataTyCon, isSynTyCon, isNewTyCon, isClosedNewTyCon, + isAlgTyCon, isDataTyCon, + isNewTyCon, unwrapNewTyCon_maybe, + isSynTyCon, isClosedSynTyCon, isOpenSynTyCon, isPrimTyCon, + isEnumerationTyCon, isGadtSyntaxTyCon, isOpenTyCon, assocTyConArgPoss_maybe, isTyConAssoc, setTyConArgPoss, isTupleTyCon, isUnboxedTupleTyCon, isBoxedTupleTyCon, tupleTyConBoxity, - isRecursiveTyCon, newTyConRep, newTyConRhs, newTyConCo_maybe, + isRecursiveTyCon, newTyConRhs, newTyConEtadRhs, newTyConCo_maybe, isHiBootTyCon, isSuperKindTyCon, isCoercionTyCon_maybe, isCoercionTyCon, + isImplicitTyCon, tcExpandTyCon_maybe, coreExpandTyCon_maybe, @@ -53,7 +61,7 @@ module TyCon( synTyConDefn, synTyConRhs, synTyConType, synTyConResKind, tyConExtName, -- External name for foreign types - maybeTyConSingleCon, + tyConSingleDataCon_maybe, -- Generics tyConHasGenerics @@ -64,15 +72,15 @@ module TyCon( import {-# SOURCE #-} TypeRep ( Kind, Type, PredType ) import {-# SOURCE #-} DataCon ( DataCon, isVanillaDataCon ) -import Var ( TyVar, Id ) -import Class ( Class ) -import BasicTypes ( Arity, RecFlag(..), Boxity(..), isBoxed ) -import Name ( Name, nameUnique, NamedThing(getName) ) -import PrelNames ( Unique, Uniquable(..) ) -import Maybe ( isJust ) -import Maybes ( orElse ) +import Var +import Class +import BasicTypes +import Name +import PrelNames +import Maybes import Outputable import FastString +import Constants \end{code} %************************************************************************ @@ -105,13 +113,6 @@ data TyCon -- types if present -- But not over the data constructors - tyConArgPoss :: Maybe [Int], -- for associated families: for each - -- tyvar in the AT decl, gives the - -- position of that tyvar in the class - -- argument list (starting from 0). - -- NB: Length is less than tyConArity - -- if higher kind signature. - algTcSelIds :: [Id], -- Its record selectors (empty if none) algTcGadtSyntax :: Bool, -- True <=> the data type was declared using GADT syntax @@ -129,7 +130,7 @@ data TyCon hasGenerics :: Bool, -- True <=> generic to/from functions are available -- (in the exports of the data type's source module) - algTcParent :: AlgTyConParent -- Gives the class or family tycon for + algTcParent :: TyConParent -- Gives the class or family tycon for -- derived tycons representing classes -- or family instances, respectively. } @@ -153,14 +154,12 @@ data TyCon tyConTyVars :: [TyVar], -- Bound tyvars - tyConArgPoss :: Maybe [Int], -- for associated families: for each - -- tyvar in the AT decl, gives the - -- position of that tyvar in the class - -- argument list (starting from 0). - -- NB: Length is less than tyConArity - -- if higher kind signature. - - synTcRhs :: SynTyConRhs -- Expanded type in here + synTcRhs :: SynTyConRhs, -- Expanded type in here + + synTcParent :: TyConParent -- Gives the family tycon of + -- representation tycons of family + -- instances + } | PrimTyCon { -- Primitive types; cannot be defined in Haskell @@ -169,7 +168,8 @@ data TyCon tyConUnique :: Unique, tyConName :: Name, tyConKind :: Kind, - tyConArity :: Arity, + tyConArity :: Arity, -- SLPJ Oct06: I'm not sure what the significance + -- of the arity of a primtycon is! primTyConRep :: PrimRep, -- Many primitive tycons are unboxed, but some are @@ -185,8 +185,10 @@ data TyCon tyConUnique :: Unique, tyConName :: Name, tyConArity :: Arity, - coKindFun :: [Type] -> Kind - } + coKindFun :: [Type] -> (Type,Type) + } -- INVARIANT: coKindFun is always applied to exactly 'arity' args + -- E.g. for trans (c1 :: ta=tb) (c2 :: tb=tc), the coKindFun returns + -- the kind as a pair of types: (ta,tc) | SuperKindTyCon { -- Super Kinds, TY (box) and CO (diamond). -- They have no kind; and arity zero @@ -196,21 +198,41 @@ data TyCon type FieldLabel = Name +-- Right hand sides of type constructors for algebraic types +-- data AlgTyConRhs - = AbstractTyCon -- We know nothing about this data type, except - -- that it's represented by a pointer - -- Used when we export a data type abstractly into - -- an hi file - | OpenDataTyCon -- data family (further instances can appear - | OpenNewTyCon -- newtype family at any time) + -- We know nothing about this data type, except that it's represented by a + -- pointer. Used when we export a data type abstractly into an hi file. + -- + = AbstractTyCon + + -- The constructor represents an open family without a fixed right hand + -- side. Additional instances can appear at any time. + -- + -- These are introduced by either a top level decl: + -- data T a :: * + -- or an assoicated data type decl, in a class decl: + -- class C a b where + -- data T b :: * + + | OpenTyCon { + + otArgPoss :: Maybe [Int] + -- Nothing <=> top-level indexed type family + -- Just ns <=> associated (not toplevel) family + -- In the latter case, for each tyvar in the AT decl, 'ns' gives the + -- position of that tyvar in the class argument list (starting from 0). + -- NB: Length is less than tyConArity iff higher kind signature. + + } | DataTyCon { data_cons :: [DataCon], -- The constructors; can be empty if the user declares -- the type to have no constructors -- INVARIANT: Kept in order of increasing tag - -- (see the tag assignment in DataCon.mkDataCon) + -- (see the tag assignment in DataCon.mkDataCon) is_enum :: Bool -- Cached: True <=> an enumeration type } -- Includes data types with no constructors. @@ -221,68 +243,78 @@ data AlgTyConRhs -- = the representation type of the tycon -- The free tyvars of this type are the tyConTyVars - nt_co :: Maybe TyCon, -- The coercion used to create the newtype + nt_co :: Maybe TyCon, -- A CoercionTyCon used to create the newtype -- from the representation - -- optional for non-recursive newtypes + -- Optional for non-recursive newtypes -- See Note [Newtype coercions] + -- Invariant: arity = #tvs in nt_etad_rhs; + -- See Note [Newtype eta] + -- Watch out! If any newtypes become transparent + -- again check Trac #1072. - nt_etad_rhs :: ([TyVar], Type) , + nt_etad_rhs :: ([TyVar], Type) -- The same again, but this time eta-reduced -- hence the [TyVar] which may be shorter than the declared -- arity of the TyCon. See Note [Newtype eta] - - nt_rep :: Type -- Cached: the *ultimate* representation type - -- By 'ultimate' I mean that the top-level constructor - -- of the rep type is not itself a newtype or type synonym. - -- The rep type isn't entirely simple: - -- for a recursive newtype we pick () as the rep type - -- newtype T = MkT T - -- - -- This one does not need to be eta reduced; hence its - -- free type variables are conveniently tyConTyVars - -- Thus: - -- newtype T a = MkT [(a,Int)] - -- The rep type is [(a,Int)] - -- NB: the rep type isn't necessarily the original RHS of the - -- newtype decl, because the rep type looks through other - } -- newtypes. + } visibleDataCons :: AlgTyConRhs -> [DataCon] visibleDataCons AbstractTyCon = [] -visibleDataCons OpenDataTyCon = [] -visibleDataCons OpenNewTyCon = [] +visibleDataCons OpenTyCon {} = [] visibleDataCons (DataTyCon{ data_cons = cs }) = cs visibleDataCons (NewTyCon{ data_con = c }) = [c] --- Both type classes as well as data/newtype family instances imply implicit +-- Both type classes as well as family instances imply implicit -- type constructors. These implicit type constructors refer to their parent -- structure (ie, the class or family from which they derive) using a type of --- the following form. --- -data AlgTyConParent = -- An ordinary type constructor has no parent. - NoParentTyCon - - -- Type constructors representing a class dictionary. - | ClassTyCon Class - - -- Type constructors representing an instances of a type - -- family. - | FamilyTyCon TyCon -- the type family - [Type] -- instance types - TyCon -- a *coercion* identifying - -- the representation type - -- with the type instance - +-- the following form. We use `TyConParent' for both algebraic and synonym +-- types, but the variant `ClassTyCon' will only be used by algebraic tycons. + +data TyConParent + = NoParentTyCon -- An ordinary type constructor has no parent. + + | ClassTyCon -- Type constructors representing a class dictionary. + Class -- INVARIANT: the classTyCon of this Class is the current tycon + + | FamilyTyCon -- Type constructors representing an instance of a type + TyCon -- The type family + [Type] -- Instance types; free variables are the tyConTyVars + -- of the current TyCon (not the family one) + -- INVARIANT: the number of types matches the arity + -- of the family tycon + TyCon -- A CoercionTyCon identifying the representation + -- type with the type instance family. + -- c.f. Note [Newtype coercions] + + -- + -- E.g. data intance T [a] = ... + -- gives a representation tycon: + -- data :R7T a = ... + -- axiom co a :: T [a] ~ :R7T a + -- with :R7T's algTcParent = FamilyTyCon T [a] co + +okParent :: Name -> TyConParent -> Bool -- Checks invariants +okParent _ NoParentTyCon = True +okParent tc_name (ClassTyCon cls) = tyConName (classTyCon cls) == tc_name +okParent _ (FamilyTyCon fam_tc tys _co_tc) = tyConArity fam_tc == length tys + +-------------------- data SynTyConRhs - = OpenSynTyCon Kind -- Type family: *result* kind given + = OpenSynTyCon Kind -- Type family: *result* kind given + (Maybe [Int]) -- for associated families: for each tyvars in + -- the AT decl, gives the position of that + -- tyvar in the class argument list (starting + -- from 0). + -- NB: Length is less than tyConArity + -- if higher kind signature. + | SynonymTyCon Type -- Mentioning head type vars. Acts as a template for -- the expansion when the tycon is applied to some - -- types. + -- types. \end{code} Note [Newtype coercions] ~~~~~~~~~~~~~~~~~~~~~~~~ - The NewTyCon field nt_co is a a TyCon (a coercion constructor in fact) which is used for coercing from the representation type of the newtype, to the newtype itself. For example, @@ -308,7 +340,7 @@ and then when we used CoT at a particular type, s, we'd say CoT @ s which encodes as (TyConApp instCoercionTyCon [TyConApp CoT [], s]) -But in GHC we instead make CoT into a new piece of type syntax +But in GHC we instead make CoT into a new piece of type syntax, CoercionTyCon, (like instCoercionTyCon, symCoercionTyCon etc), which must always be saturated, but which encodes as TyConApp CoT [s] @@ -340,12 +372,53 @@ Source code: w2 :: Foo T w2 = MkFoo (\(MkT x) -> case w1 of MkFoo f -> f x) -After desugaring, and discading the data constructors for the newtypes, +After desugaring, and discarding the data constructors for the newtypes, we get: w2 :: Foo T w2 = w1 And now Lint complains unless Foo T == Foo [], and that requires T==[] +This point carries over to the newtype coercion, because we need to +say + w2 = w1 `cast` Foo CoT + +so the coercion tycon CoT must have + kind: T ~ [] + and arity: 0 + + +Note [Indexed data types] (aka data type families) +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + See also Note [Wrappers for data instance tycons] in MkId.lhs + +Consider + data family T a + + data instance T (b,c) where + T1 :: b -> c -> T (b,c) + +Then + * T is the "family TyCon" + + * We make "representation TyCon" :R1T, thus: + data :R1T b c where + T1 :: forall b c. b -> c -> :R1T b c + + * It has a top-level coercion connecting it to the family TyCon + + axiom :Co:R1T b c : T (b,c) ~ :R1T b c + + * The data contructor T1 has a wrapper (which is what the source-level + "T1" invokes): + + $WT1 :: forall b c. b -> c -> T (b,c) + $WT1 b c (x::b) (y::c) = T1 b c x y `cast` sym (:Co:R1T b c) + + * The representation TyCon :R1T has an AlgTyConParent of + + FamilyTyCon T [(b,c)] :Co:R1T + + %************************************************************************ %* * @@ -382,6 +455,22 @@ data PrimRep | AddrRep -- a pointer, but not to a Haskell value | FloatRep | DoubleRep + deriving( Eq, Show ) + +instance Outputable PrimRep where + ppr r = text (show r) + +-- Size of a PrimRep, in words +primRepSizeW :: PrimRep -> Int +primRepSizeW IntRep = 1 +primRepSizeW WordRep = 1 +primRepSizeW Int64Rep = wORD64_SIZE `quot` wORD_SIZE +primRepSizeW Word64Rep= wORD64_SIZE `quot` wORD_SIZE +primRepSizeW FloatRep = 1 -- NB. might not take a full word +primRepSizeW DoubleRep= dOUBLE_SIZE `quot` wORD_SIZE +primRepSizeW AddrRep = 1 +primRepSizeW PtrRep = 1 +primRepSizeW VoidRep = 0 \end{code} %************************************************************************ @@ -409,6 +498,17 @@ mkFunTyCon name kind -- This is the making of a TyCon. Just the same as the old mkAlgTyCon, -- but now you also have to pass in the generic information about the type -- constructor - you can get hold of it easily (see Generics module) +mkAlgTyCon :: Name + -> Kind + -> [TyVar] + -> [PredType] + -> AlgTyConRhs + -> [Id] + -> TyConParent + -> RecFlag + -> Bool + -> Bool + -> TyCon mkAlgTyCon name kind tyvars stupid rhs sel_ids parent is_rec gen_info gadt_syn = AlgTyCon { tyConName = name, @@ -416,19 +516,20 @@ mkAlgTyCon name kind tyvars stupid rhs sel_ids parent is_rec gen_info gadt_syn tyConKind = kind, tyConArity = length tyvars, tyConTyVars = tyvars, - tyConArgPoss = Nothing, algTcStupidTheta = stupid, algTcRhs = rhs, algTcSelIds = sel_ids, - algTcParent = parent, + algTcParent = ASSERT( okParent name parent ) parent, algTcRec = is_rec, algTcGadtSyntax = gadt_syn, hasGenerics = gen_info } +mkClassTyCon :: Name -> Kind -> [TyVar] -> AlgTyConRhs -> Class -> RecFlag -> TyCon mkClassTyCon name kind tyvars rhs clas is_rec = mkAlgTyCon name kind tyvars [] rhs [] (ClassTyCon clas) is_rec False False +mkTupleTyCon :: Name -> Kind -> Arity -> [TyVar] -> DataCon -> Boxity -> Bool -> TyCon mkTupleTyCon name kind arity tyvars con boxed gen_info = TupleTyCon { tyConUnique = nameUnique name, @@ -445,6 +546,7 @@ mkTupleTyCon name kind arity tyvars con boxed gen_info -- as primitive, but *lifted*, TyCons for now. They are lifted -- because the Haskell type T representing the (foreign) .NET -- type T is actually implemented (in ILX) as a thunk +mkForeignTyCon :: Name -> Maybe FastString -> Kind -> Arity -> TyCon mkForeignTyCon name ext_name kind arity = PrimTyCon { tyConName = name, @@ -458,16 +560,20 @@ mkForeignTyCon name ext_name kind arity -- most Prim tycons are lifted +mkPrimTyCon :: Name -> Kind -> Arity -> PrimRep -> TyCon mkPrimTyCon name kind arity rep = mkPrimTyCon' name kind arity rep True +mkVoidPrimTyCon :: Name -> Kind -> Arity -> TyCon mkVoidPrimTyCon name kind arity = mkPrimTyCon' name kind arity VoidRep True -- but RealWorld is lifted +mkLiftedPrimTyCon :: Name -> Kind -> Arity -> PrimRep -> TyCon mkLiftedPrimTyCon name kind arity rep = mkPrimTyCon' name kind arity rep False +mkPrimTyCon' :: Name -> Kind -> Arity -> PrimRep -> Bool -> TyCon mkPrimTyCon' name kind arity rep is_unlifted = PrimTyCon { tyConName = name, @@ -479,17 +585,19 @@ mkPrimTyCon' name kind arity rep is_unlifted tyConExtName = Nothing } -mkSynTyCon name kind tyvars rhs +mkSynTyCon :: Name -> Kind -> [TyVar] -> SynTyConRhs -> TyConParent -> TyCon +mkSynTyCon name kind tyvars rhs parent = SynTyCon { tyConName = name, tyConUnique = nameUnique name, tyConKind = kind, tyConArity = length tyvars, tyConTyVars = tyvars, - tyConArgPoss = Nothing, - synTcRhs = rhs + synTcRhs = rhs, + synTcParent = parent } +mkCoercionTyCon :: Name -> Arity -> ([Type] -> (Type,Type)) -> TyCon mkCoercionTyCon name arity kindRule = CoercionTyCon { tyConName = name, @@ -499,6 +607,7 @@ mkCoercionTyCon name arity kindRule } -- Super kinds always have arity zero +mkSuperKindTyCon :: Name -> TyCon mkSuperKindTyCon name = SuperKindTyCon { tyConName = name, @@ -532,40 +641,40 @@ isUnLiftedTyCon _ = False isAlgTyCon :: TyCon -> Bool isAlgTyCon (AlgTyCon {}) = True isAlgTyCon (TupleTyCon {}) = True -isAlgTyCon other = False +isAlgTyCon _ = False isDataTyCon :: TyCon -> Bool --- isDataTyCon returns True for data types that are represented by --- heap-allocated constructors. +-- isDataTyCon returns True for data types that are definitely +-- represented by heap-allocated constructors. -- These are srcutinised by Core-level @case@ expressions, and they -- get info tables allocated for them. -- True for all @data@ types -- False for newtypes -- unboxed tuples -isDataTyCon tc@(AlgTyCon {algTcRhs = rhs}) +-- type families +-- +-- NB: for a data type family, T, only the *instance* tycons are +-- get an info table etc. The family tycon does not. +-- Hence False for OpenTyCon +isDataTyCon (AlgTyCon {algTcRhs = rhs}) = case rhs of - OpenDataTyCon -> True + OpenTyCon {} -> False DataTyCon {} -> True - OpenNewTyCon -> False NewTyCon {} -> False - AbstractTyCon -> pprPanic "isDataTyCon" (ppr tc) + AbstractTyCon -> False -- We don't know, so return False isDataTyCon (TupleTyCon {tyConBoxed = boxity}) = isBoxed boxity -isDataTyCon other = False +isDataTyCon _ = False isNewTyCon :: TyCon -> Bool -isNewTyCon (AlgTyCon {algTcRhs = rhs}) = case rhs of - OpenNewTyCon -> True - NewTyCon {} -> True - _ -> False -isNewTyCon other = False - --- This is an important refinement as typical newtype optimisations do *not* --- hold for newtype families. Why? Given a type `T a', if T is a newtype --- family, there is no unique right hand side by which `T a' can be replaced --- by a cast. --- -isClosedNewTyCon :: TyCon -> Bool -isClosedNewTyCon tycon = isNewTyCon tycon && not (isOpenTyCon tycon) +isNewTyCon (AlgTyCon {algTcRhs = NewTyCon {}}) = True +isNewTyCon _ = False + +unwrapNewTyCon_maybe :: TyCon -> Maybe ([TyVar], Type, Maybe TyCon) +unwrapNewTyCon_maybe (AlgTyCon { tyConTyVars = tvs, + algTcRhs = NewTyCon { nt_co = mb_co, + nt_rhs = rhs }}) + = Just (tvs, rhs, mb_co) +unwrapNewTyCon_maybe _ = Nothing isProductTyCon :: TyCon -> Bool -- A "product" tycon @@ -580,39 +689,51 @@ isProductTyCon tc@(AlgTyCon {}) = case algTcRhs tc of DataTyCon{ data_cons = [data_con] } -> isVanillaDataCon data_con NewTyCon {} -> True - other -> False + _ -> False isProductTyCon (TupleTyCon {}) = True -isProductTyCon other = False +isProductTyCon _ = False isSynTyCon :: TyCon -> Bool isSynTyCon (SynTyCon {}) = True isSynTyCon _ = False +-- As for newtypes, it is in some contexts important to distinguish between +-- closed synonyms and synonym families, as synonym families have no unique +-- right hand side to which a synonym family application can expand. +-- +isClosedSynTyCon :: TyCon -> Bool +isClosedSynTyCon tycon = isSynTyCon tycon && not (isOpenTyCon tycon) + +isOpenSynTyCon :: TyCon -> Bool +isOpenSynTyCon tycon = isSynTyCon tycon && isOpenTyCon tycon + isGadtSyntaxTyCon :: TyCon -> Bool isGadtSyntaxTyCon (AlgTyCon { algTcGadtSyntax = res }) = res -isGadtSyntaxTyCon other = False +isGadtSyntaxTyCon _ = False isEnumerationTyCon :: TyCon -> Bool isEnumerationTyCon (AlgTyCon {algTcRhs = DataTyCon { is_enum = res }}) = res -isEnumerationTyCon other = False +isEnumerationTyCon _ = False isOpenTyCon :: TyCon -> Bool -isOpenTyCon (SynTyCon {synTcRhs = OpenSynTyCon _}) = True -isOpenTyCon (AlgTyCon {algTcRhs = OpenDataTyCon }) = True -isOpenTyCon (AlgTyCon {algTcRhs = OpenNewTyCon }) = True -isOpenTyCon _ = False +isOpenTyCon (SynTyCon {synTcRhs = OpenSynTyCon _ _}) = True +isOpenTyCon (AlgTyCon {algTcRhs = OpenTyCon {} }) = True +isOpenTyCon _ = False assocTyConArgPoss_maybe :: TyCon -> Maybe [Int] -assocTyConArgPoss_maybe (AlgTyCon { tyConArgPoss = poss }) = poss -assocTyConArgPoss_maybe (SynTyCon { tyConArgPoss = poss }) = poss -assocTyConArgPoss_maybe _ = Nothing +assocTyConArgPoss_maybe (AlgTyCon { + algTcRhs = OpenTyCon {otArgPoss = poss}}) = poss +assocTyConArgPoss_maybe (SynTyCon { synTcRhs = OpenSynTyCon _ poss }) = poss +assocTyConArgPoss_maybe _ = Nothing isTyConAssoc :: TyCon -> Bool isTyConAssoc = isJust . assocTyConArgPoss_maybe setTyConArgPoss :: TyCon -> [Int] -> TyCon -setTyConArgPoss tc@(AlgTyCon {}) poss = tc { tyConArgPoss = Just poss } -setTyConArgPoss tc@(SynTyCon {}) poss = tc { tyConArgPoss = Just poss } +setTyConArgPoss tc@(AlgTyCon { algTcRhs = rhs }) poss = + tc { algTcRhs = rhs {otArgPoss = Just poss} } +setTyConArgPoss tc@(SynTyCon { synTcRhs = OpenSynTyCon ki _ }) poss = + tc { synTcRhs = OpenSynTyCon ki (Just poss) } setTyConArgPoss tc _ = pprPanic "setTyConArgPoss" (ppr tc) isTupleTyCon :: TyCon -> Bool @@ -625,43 +746,65 @@ isTupleTyCon :: TyCon -> Bool -- get spat into the interface file as tuple tycons, so I don't think -- it matters. isTupleTyCon (TupleTyCon {}) = True -isTupleTyCon other = False +isTupleTyCon _ = False isUnboxedTupleTyCon :: TyCon -> Bool isUnboxedTupleTyCon (TupleTyCon {tyConBoxed = boxity}) = not (isBoxed boxity) -isUnboxedTupleTyCon other = False +isUnboxedTupleTyCon _ = False isBoxedTupleTyCon :: TyCon -> Bool isBoxedTupleTyCon (TupleTyCon {tyConBoxed = boxity}) = isBoxed boxity -isBoxedTupleTyCon other = False +isBoxedTupleTyCon _ = False +tupleTyConBoxity :: TyCon -> Boxity tupleTyConBoxity tc = tyConBoxed tc isRecursiveTyCon :: TyCon -> Bool isRecursiveTyCon (AlgTyCon {algTcRec = Recursive}) = True -isRecursiveTyCon other = False +isRecursiveTyCon _ = False isHiBootTyCon :: TyCon -> Bool -- Used for knot-tying in hi-boot files isHiBootTyCon (AlgTyCon {algTcRhs = AbstractTyCon}) = True -isHiBootTyCon other = False +isHiBootTyCon _ = False isForeignTyCon :: TyCon -> Bool -- isForeignTyCon identifies foreign-imported type constructors isForeignTyCon (PrimTyCon {tyConExtName = Just _}) = True -isForeignTyCon other = False +isForeignTyCon _ = False isSuperKindTyCon :: TyCon -> Bool isSuperKindTyCon (SuperKindTyCon {}) = True -isSuperKindTyCon other = False +isSuperKindTyCon _ = False -isCoercionTyCon_maybe :: TyCon -> Maybe (Arity, [Type] -> Kind) +isCoercionTyCon_maybe :: TyCon -> Maybe (Arity, [Type] -> (Type,Type)) isCoercionTyCon_maybe (CoercionTyCon {tyConArity = ar, coKindFun = rule}) = Just (ar, rule) -isCoercionTyCon_maybe other = Nothing +isCoercionTyCon_maybe _ = Nothing +isCoercionTyCon :: TyCon -> Bool isCoercionTyCon (CoercionTyCon {}) = True -isCoercionTyCon other = False +isCoercionTyCon _ = False + +-- Identifies implicit tycons that, in particular, do not go into interface +-- files (because they are implicitly reconstructed when the interface is +-- read). +-- +-- Note that +-- +-- * associated families are implicit, as they are re-constructed from +-- the class declaration in which they reside, and +-- * family instances are *not* implicit as they represent the instance body +-- (similar to a dfun does that for a class instance). +-- +isImplicitTyCon :: TyCon -> Bool +isImplicitTyCon tycon | isTyConAssoc tycon = True + | isSynTyCon tycon = False + | isAlgTyCon tycon = isClassTyCon tycon || + isTupleTyCon tycon +isImplicitTyCon _other = True + -- catches: FunTyCon, PrimTyCon, + -- CoercionTyCon, SuperKindTyCon \end{code} @@ -677,11 +820,11 @@ tcExpandTyCon_maybe, coreExpandTyCon_maybe Type, -- Body type (not yet substituted) [Type]) -- Leftover args --- For the *typechecker* view, we expand synonyms only +-- For the *typechecker* view, we expand (closed) synonyms only tcExpandTyCon_maybe (SynTyCon {tyConTyVars = tvs, synTcRhs = SynonymTyCon rhs }) tys = expand tvs rhs tys -tcExpandTyCon_maybe other_tycon tys = Nothing +tcExpandTyCon_maybe _ _ = Nothing --------------- -- For the *Core* view, we expand synonyms only as well @@ -712,7 +855,7 @@ expand tvs rhs tys tyConHasGenerics :: TyCon -> Bool tyConHasGenerics (AlgTyCon {hasGenerics = hg}) = hg tyConHasGenerics (TupleTyCon {hasGenerics = hg}) = hg -tyConHasGenerics other = False -- Synonyms +tyConHasGenerics _ = False -- Synonyms tyConDataCons :: TyCon -> [DataCon] -- It's convenient for tyConDataCons to return the @@ -723,21 +866,19 @@ tyConDataCons_maybe :: TyCon -> Maybe [DataCon] tyConDataCons_maybe (AlgTyCon {algTcRhs = DataTyCon { data_cons = cons }}) = Just cons tyConDataCons_maybe (AlgTyCon {algTcRhs = NewTyCon { data_con = con }}) = Just [con] tyConDataCons_maybe (TupleTyCon {dataCon = con}) = Just [con] -tyConDataCons_maybe other = Nothing +tyConDataCons_maybe _ = Nothing tyConFamilySize :: TyCon -> Int tyConFamilySize (AlgTyCon {algTcRhs = DataTyCon {data_cons = cons}}) = length cons tyConFamilySize (AlgTyCon {algTcRhs = NewTyCon {}}) = 1 -tyConFamilySize (AlgTyCon {algTcRhs = OpenDataTyCon}) = 0 +tyConFamilySize (AlgTyCon {algTcRhs = OpenTyCon {}}) = 0 tyConFamilySize (TupleTyCon {}) = 1 -#ifdef DEBUG tyConFamilySize other = pprPanic "tyConFamilySize:" (ppr other) -#endif tyConSelIds :: TyCon -> [Id] tyConSelIds (AlgTyCon {algTcSelIds = fs}) = fs -tyConSelIds other_tycon = [] +tyConSelIds _ = [] algTyConRhs :: TyCon -> AlgTyConRhs algTyConRhs (AlgTyCon {algTcRhs = rhs}) = rhs @@ -750,9 +891,9 @@ newTyConRhs :: TyCon -> ([TyVar], Type) newTyConRhs (AlgTyCon {tyConTyVars = tvs, algTcRhs = NewTyCon { nt_rhs = rhs }}) = (tvs, rhs) newTyConRhs tycon = pprPanic "newTyConRhs" (ppr tycon) -newTyConRep :: TyCon -> ([TyVar], Type) -newTyConRep (AlgTyCon {tyConTyVars = tvs, algTcRhs = NewTyCon { nt_rep = rep }}) = (tvs, rep) -newTyConRep tycon = pprPanic "newTyConRep" (ppr tycon) +newTyConEtadRhs :: TyCon -> ([TyVar], Type) +newTyConEtadRhs (AlgTyCon {algTcRhs = NewTyCon { nt_etad_rhs = tvs_rhs }}) = tvs_rhs +newTyConEtadRhs tycon = pprPanic "newTyConEtadRhs" (ppr tycon) newTyConCo_maybe :: TyCon -> Maybe TyCon newTyConCo_maybe (AlgTyCon {algTcRhs = NewTyCon { nt_co = co }}) = co @@ -786,44 +927,49 @@ synTyConType tc = case synTcRhs tc of _ -> pprPanic "synTyConType" (ppr tc) synTyConResKind :: TyCon -> Kind -synTyConResKind (SynTyCon {synTcRhs = OpenSynTyCon kind}) = kind +synTyConResKind (SynTyCon {synTcRhs = OpenSynTyCon kind _}) = kind synTyConResKind tycon = pprPanic "synTyConResKind" (ppr tycon) \end{code} \begin{code} -maybeTyConSingleCon :: TyCon -> Maybe DataCon -maybeTyConSingleCon (AlgTyCon {algTcRhs = DataTyCon {data_cons = [c] }}) = Just c -maybeTyConSingleCon (AlgTyCon {algTcRhs = NewTyCon { data_con = c }}) = Just c -maybeTyConSingleCon (AlgTyCon {}) = Nothing -maybeTyConSingleCon (TupleTyCon {dataCon = con}) = Just con -maybeTyConSingleCon (PrimTyCon {}) = Nothing -maybeTyConSingleCon (FunTyCon {}) = Nothing -- case at funty -maybeTyConSingleCon tc = pprPanic "maybeTyConSingleCon: unexpected tycon " $ ppr tc +tyConSingleDataCon_maybe :: TyCon -> Maybe DataCon +tyConSingleDataCon_maybe (AlgTyCon {algTcRhs = DataTyCon {data_cons = [c] }}) = Just c +tyConSingleDataCon_maybe (AlgTyCon {algTcRhs = NewTyCon { data_con = c }}) = Just c +tyConSingleDataCon_maybe (AlgTyCon {}) = Nothing +tyConSingleDataCon_maybe (TupleTyCon {dataCon = con}) = Just con +tyConSingleDataCon_maybe (PrimTyCon {}) = Nothing +tyConSingleDataCon_maybe (FunTyCon {}) = Nothing -- case at funty +tyConSingleDataCon_maybe tc = pprPanic "tyConSingleDataCon_maybe: unexpected tycon " $ ppr tc \end{code} \begin{code} isClassTyCon :: TyCon -> Bool isClassTyCon (AlgTyCon {algTcParent = ClassTyCon _}) = True -isClassTyCon other_tycon = False +isClassTyCon _ = False tyConClass_maybe :: TyCon -> Maybe Class tyConClass_maybe (AlgTyCon {algTcParent = ClassTyCon clas}) = Just clas -tyConClass_maybe ther_tycon = Nothing +tyConClass_maybe _ = Nothing isFamInstTyCon :: TyCon -> Bool isFamInstTyCon (AlgTyCon {algTcParent = FamilyTyCon _ _ _ }) = True -isFamInstTyCon other_tycon = False +isFamInstTyCon (SynTyCon {synTcParent = FamilyTyCon _ _ _ }) = True +isFamInstTyCon _ = False tyConFamInst_maybe :: TyCon -> Maybe (TyCon, [Type]) tyConFamInst_maybe (AlgTyCon {algTcParent = FamilyTyCon fam instTys _}) = Just (fam, instTys) -tyConFamInst_maybe ther_tycon = +tyConFamInst_maybe (SynTyCon {synTcParent = FamilyTyCon fam instTys _}) = + Just (fam, instTys) +tyConFamInst_maybe _ = Nothing tyConFamilyCoercion_maybe :: TyCon -> Maybe TyCon tyConFamilyCoercion_maybe (AlgTyCon {algTcParent = FamilyTyCon _ _ coe}) = Just coe -tyConFamilyCoercion_maybe ther_tycon = +tyConFamilyCoercion_maybe (SynTyCon {synTcParent = FamilyTyCon _ _ coe}) = + Just coe +tyConFamilyCoercion_maybe _ = Nothing \end{code}