X-Git-Url: http://git.megacz.com/?p=ghc-hetmet.git;a=blobdiff_plain;f=compiler%2FbasicTypes%2FDataCon.lhs;h=406d02a9df17207d3fc43c4f9ac81fd0cfa20a04;hp=1b354c65ddcf1c44098557a7001e288e477b05a9;hb=215ce9f15215399ce30ae55c9521087847d78646;hpb=5e5310b3cb4f78e30cc7b90879eb016e97c214cb diff --git a/compiler/basicTypes/DataCon.lhs b/compiler/basicTypes/DataCon.lhs index 1b354c6..406d02a 100644 --- a/compiler/basicTypes/DataCon.lhs +++ b/compiler/basicTypes/DataCon.lhs @@ -15,9 +15,11 @@ module DataCon ( -- ** Type deconstruction dataConRepType, dataConSig, dataConFullSig, - dataConName, dataConIdentity, dataConTag, dataConTyCon, dataConUserType, + dataConName, dataConIdentity, dataConTag, dataConTyCon, + dataConOrigTyCon, dataConUserType, dataConUnivTyVars, dataConExTyVars, dataConAllTyVars, - dataConEqSpec, eqSpecPreds, dataConEqTheta, dataConDictTheta, dataConStupidTheta, + dataConEqSpec, eqSpecPreds, dataConEqTheta, dataConDictTheta, + dataConStupidTheta, dataConInstArgTys, dataConOrigArgTys, dataConOrigResTy, dataConInstOrigArgTys, dataConRepArgTys, dataConFieldLabels, dataConFieldType, @@ -49,10 +51,10 @@ import Outputable import Unique import ListSetOps import Util -import Maybes import FastString import Module +import qualified Data.Data as Data import Data.Char import Data.Word import Data.List ( partition ) @@ -96,12 +98,12 @@ Note [Data Constructor Naming] ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Each data constructor C has two, and possibly up to four, Names associated with it: - OccName Name space Name of - --------------------------------------------------------------------------- - * The "data con itself" C DataName DataCon - * The "worker data con" C VarName Id (the worker) - * The "wrapper data con" \$WC VarName Id (the wrapper) - * The "newtype coercion" :CoT TcClsName TyCon + OccName Name space Name of Notes + --------------------------------------------------------------------------- + The "data con itself" C DataName DataCon In dom( GlobalRdrEnv ) + The "worker data con" C VarName Id The worker + The "wrapper data con" $WC VarName Id The wrapper + The "newtype coercion" :CoT TcClsName TyCon EVERY data constructor (incl for newtypes) has the former two (the data con itself, and its worker. But only some data constructors have a @@ -269,8 +271,9 @@ data DataCon -- syntax, provided its type looks like the above. -- The declaration format is held in the TyCon (algTcGadtSyntax) - dcUnivTyVars :: [TyVar], -- Universally-quantified type vars + dcUnivTyVars :: [TyVar], -- Universally-quantified type vars [a,b,c] -- INVARIANT: length matches arity of the dcRepTyCon + --- result type of (rep) data con is exactly (T a b c) dcExTyVars :: [TyVar], -- Existentially-quantified type vars -- In general, the dcUnivTyVars are NOT NECESSARILY THE SAME AS THE TYVARS @@ -317,14 +320,14 @@ data DataCon dcOrigArgTys :: [Type], -- Original argument types -- (before unboxing and flattening of strict fields) - dcOrigResTy :: Type, -- Original result type + dcOrigResTy :: Type, -- Original result type, as seen by the user -- NB: for a data instance, the original user result type may -- differ from the DataCon's representation TyCon. Example -- data instance T [a] where MkT :: a -> T [a] -- The OrigResTy is T [a], but the dcRepTyCon might be :T123 -- Now the strictness annotations and field labels of the constructor - dcStrictMarks :: [StrictnessMark], + dcStrictMarks :: [HsBang], -- Strictness annotations as decided by the compiler. -- Does *not* include the existential dictionaries -- length = dataConSourceArity dataCon @@ -339,7 +342,8 @@ data DataCon -- after unboxing and flattening, -- and *including* existential dictionaries - dcRepStrictness :: [StrictnessMark], -- One for each *representation* argument + dcRepStrictness :: [StrictnessMark], + -- One for each *representation* *value* argument -- See also Note [Data-con worker strictness] in MkId.lhs -- Result type of constructor is T t1..tn @@ -452,6 +456,15 @@ instance Outputable DataCon where instance Show DataCon where showsPrec p con = showsPrecSDoc p (ppr con) + +instance Data.Typeable DataCon where + typeOf _ = Data.mkTyConApp (Data.mkTyCon "DataCon") [] + +instance Data.Data DataCon where + -- don't traverse? + toConstr _ = abstractConstr "DataCon" + gunfold _ _ = error "gunfold" + dataTypeOf _ = mkNoRepType "DataCon" \end{code} @@ -465,15 +478,18 @@ instance Show DataCon where -- | Build a new data constructor mkDataCon :: Name -> Bool -- ^ Is the constructor declared infix? - -> [StrictnessMark] -- ^ Strictness annotations written in the source file - -> [FieldLabel] -- ^ Field labels for the constructor, if it is a record, otherwise empty + -> [HsBang] -- ^ Strictness annotations written in the source file + -> [FieldLabel] -- ^ Field labels for the constructor, if it is a record, + -- otherwise empty -> [TyVar] -- ^ Universally quantified type variables -> [TyVar] -- ^ Existentially quantified type variables -> [(TyVar,Type)] -- ^ GADT equalities -> ThetaType -- ^ Theta-type occuring before the arguments proper - -> [Type] -- ^ Argument types - -> TyCon -- ^ Type constructor we are for - -> ThetaType -- ^ The "stupid theta", context of the data declaration e.g. @data Eq a => T a ...@ + -> [Type] -- ^ Original argument types + -> Type -- ^ Original result type + -> TyCon -- ^ Representation type constructor + -> ThetaType -- ^ The "stupid theta", context of the data declaration + -- e.g. @data Eq a => T a ...@ -> DataConIds -- ^ The Ids of the actual builder functions -> DataCon -- Can get the tag from the TyCon @@ -483,7 +499,7 @@ mkDataCon name declared_infix fields univ_tvs ex_tvs eq_spec theta - orig_arg_tys tycon + orig_arg_tys orig_res_ty rep_tycon stupid_theta ids -- Warning: mkDataCon is not a good place to check invariants. -- If the programmer writes the wrong result type in the decl, thus: @@ -506,7 +522,7 @@ mkDataCon name declared_infix dcStupidTheta = stupid_theta, dcEqTheta = eq_theta, dcDictTheta = dict_theta, dcOrigArgTys = orig_arg_tys, dcOrigResTy = orig_res_ty, - dcRepTyCon = tycon, + dcRepTyCon = rep_tycon, dcRepArgTys = rep_arg_tys, dcStrictMarks = arg_stricts, dcRepStrictness = rep_arg_stricts, @@ -525,21 +541,11 @@ mkDataCon name declared_infix real_arg_tys = dict_tys ++ orig_arg_tys real_stricts = map mk_dict_strict_mark dict_theta ++ arg_stricts - -- Example - -- data instance T (b,c) where - -- TI :: forall e. e -> T (e,e) - -- - -- The representation tycon looks like this: - -- data :R7T b c where - -- TI :: forall b1 c1. (b1 ~ c1) => b1 -> :R7T b1 c1 - -- In this case orig_res_ty = T (e,e) - orig_res_ty = mkFamilyTyConApp tycon (substTyVars (mkTopTvSubst eq_spec) univ_tvs) - -- Representation arguments and demands -- To do: eliminate duplication with MkId (rep_arg_stricts, rep_arg_tys) = computeRep real_stricts real_arg_tys - tag = assoc "mkDataCon" (tyConDataCons tycon `zip` [fIRST_TAG..]) con + tag = assoc "mkDataCon" (tyConDataCons rep_tycon `zip` [fIRST_TAG..]) con ty = mkForAllTys univ_tvs $ mkForAllTys ex_tvs $ mkFunTys (mkPredTys (eqSpecPreds eq_spec)) $ mkFunTys (mkPredTys eq_theta) $ @@ -547,14 +553,14 @@ mkDataCon name declared_infix -- because they might be flattened.. -- but the equality predicates are not mkFunTys rep_arg_tys $ - mkTyConApp tycon (mkTyVarTys univ_tvs) + mkTyConApp rep_tycon (mkTyVarTys univ_tvs) eqSpecPreds :: [(TyVar,Type)] -> ThetaType eqSpecPreds spec = [ mkEqPred (mkTyVarTy tv, ty) | (tv,ty) <- spec ] -mk_dict_strict_mark :: PredType -> StrictnessMark -mk_dict_strict_mark pred | isStrictPred pred = MarkedStrict - | otherwise = NotMarkedStrict +mk_dict_strict_mark :: PredType -> HsBang +mk_dict_strict_mark pred | isStrictPred pred = HsStrict + | otherwise = HsNoBang \end{code} \begin{code} @@ -570,6 +576,14 @@ dataConTag = dcTag dataConTyCon :: DataCon -> TyCon dataConTyCon = dcRepTyCon +-- | The original type constructor used in the definition of this data +-- constructor. In case of a data family instance, that will be the family +-- type constructor. +dataConOrigTyCon :: DataCon -> TyCon +dataConOrigTyCon dc + | Just (tc, _) <- tyConFamInst_maybe (dcRepTyCon dc) = tc + | otherwise = dcRepTyCon dc + -- | The representation type of the data constructor, i.e. the sort -- type that will represent values of this type at runtime dataConRepType :: DataCon -> Type @@ -642,16 +656,18 @@ dataConFieldLabels = dcFields -- | Extract the type for any given labelled field of the 'DataCon' dataConFieldType :: DataCon -> FieldLabel -> Type -dataConFieldType con label = expectJust "unexpected label" $ - lookup label (dcFields con `zip` dcOrigArgTys con) +dataConFieldType con label + = case lookup label (dcFields con `zip` dcOrigArgTys con) of + Just ty -> ty + Nothing -> pprPanic "dataConFieldType" (ppr con <+> ppr label) -- | The strictness markings decided on by the compiler. Does not include those for -- existential dictionaries. The list is in one-to-one correspondence with the arity of the 'DataCon' -dataConStrictMarks :: DataCon -> [StrictnessMark] +dataConStrictMarks :: DataCon -> [HsBang] dataConStrictMarks = dcStrictMarks -- | Strictness of /existential/ arguments only -dataConExStricts :: DataCon -> [StrictnessMark] +dataConExStricts :: DataCon -> [HsBang] -- Usually empty, so we don't bother to cache this dataConExStricts dc = map mk_dict_strict_mark $ dcDictTheta dc @@ -690,7 +706,8 @@ dataConRepStrictness dc = dcRepStrictness dc -- 4) The /original/ result type of the 'DataCon' dataConSig :: DataCon -> ([TyVar], ThetaType, [Type], Type) dataConSig (MkData {dcUnivTyVars = univ_tvs, dcExTyVars = ex_tvs, dcEqSpec = eq_spec, - dcEqTheta = eq_theta, dcDictTheta = dict_theta, dcOrigArgTys = arg_tys, dcOrigResTy = res_ty}) + dcEqTheta = eq_theta, dcDictTheta = dict_theta, + dcOrigArgTys = arg_tys, dcOrigResTy = res_ty}) = (univ_tvs ++ ex_tvs, eqSpecPreds eq_spec ++ eq_theta ++ dict_theta, arg_tys, res_ty) -- | The \"full signature\" of the 'DataCon' returns, in order: @@ -703,13 +720,15 @@ dataConSig (MkData {dcUnivTyVars = univ_tvs, dcExTyVars = ex_tvs, dcEqSpec = eq_ -- -- 4) The result of 'dataConDictTheta' -- --- 5) The original argument types to the 'DataCon' (i.e. before any change of the representation of the type) +-- 5) The original argument types to the 'DataCon' (i.e. before +-- any change of the representation of the type) -- -- 6) The original result type of the 'DataCon' dataConFullSig :: DataCon -> ([TyVar], [TyVar], [(TyVar,Type)], ThetaType, ThetaType, [Type], Type) dataConFullSig (MkData {dcUnivTyVars = univ_tvs, dcExTyVars = ex_tvs, dcEqSpec = eq_spec, - dcEqTheta = eq_theta, dcDictTheta = dict_theta, dcOrigArgTys = arg_tys, dcOrigResTy = res_ty}) + dcEqTheta = eq_theta, dcDictTheta = dict_theta, + dcOrigArgTys = arg_tys, dcOrigResTy = res_ty}) = (univ_tvs, ex_tvs, eq_spec, eq_theta, dict_theta, arg_tys, res_ty) dataConOrigResTy :: DataCon -> Type @@ -729,7 +748,7 @@ dataConUserType :: DataCon -> Type -- -- rather than: -- --- > T :: forall a c. forall b. (c=[a]) => a -> b -> T c +-- > T :: forall a c. forall b. (c~[a]) => a -> b -> T c -- -- NB: If the constructor is part of a data instance, the result type -- mentions the family tycon, not the internal one. @@ -894,7 +913,7 @@ deepSplitProductType str ty Nothing -> pprPanic (str ++ ": not a product") (pprType ty) -- | Compute the representation type strictness and type suitable for a 'DataCon' -computeRep :: [StrictnessMark] -- ^ Original argument strictness +computeRep :: [HsBang] -- ^ Original argument strictness -> [Type] -- ^ Original argument types -> ([StrictnessMark], -- Representation arg strictness [Type]) -- And type @@ -902,10 +921,11 @@ computeRep :: [StrictnessMark] -- ^ Original argument strictness computeRep stricts tys = unzip $ concat $ zipWithEqual "computeRep" unbox stricts tys where - unbox NotMarkedStrict ty = [(NotMarkedStrict, ty)] - unbox MarkedStrict ty = [(MarkedStrict, ty)] - unbox MarkedUnboxed ty = zipEqual "computeRep" (dataConRepStrictness arg_dc) arg_tys - where - (_tycon, _tycon_args, arg_dc, arg_tys) - = deepSplitProductType "unbox_strict_arg_ty" ty + unbox HsNoBang ty = [(NotMarkedStrict, ty)] + unbox HsStrict ty = [(MarkedStrict, ty)] + unbox HsUnpackFailed ty = [(MarkedStrict, ty)] + unbox HsUnpack ty = zipEqual "computeRep" (dataConRepStrictness arg_dc) arg_tys + where + (_tycon, _tycon_args, arg_dc, arg_tys) + = deepSplitProductType "unbox_strict_arg_ty" ty \end{code}