X-Git-Url: http://git.megacz.com/?a=blobdiff_plain;f=compiler%2FhsSyn%2FHsDecls.lhs;h=54075d4f92f88a2bceb42015191fae1cc0cc7c07;hb=82c4d36b187955e3cedbb11cff92688747773456;hp=070079e6a6cbb0a4ee9735bb63225aeb67129453;hpb=afef39736dcde6f4947a6f362f9e6b3586933db4;p=ghc-hetmet.git diff --git a/compiler/hsSyn/HsDecls.lhs b/compiler/hsSyn/HsDecls.lhs index 070079e..54075d4 100644 --- a/compiler/hsSyn/HsDecls.lhs +++ b/compiler/hsSyn/HsDecls.lhs @@ -18,7 +18,8 @@ module HsDecls ( DeprecDecl(..), LDeprecDecl, HsGroup(..), emptyRdrGroup, emptyRnGroup, appendGroups, tcdName, tyClDeclNames, tyClDeclTyVars, - isClassDecl, isSynDecl, isDataDecl, + isClassDecl, isTFunDecl, isSynDecl, isDataDecl, isKindSigDecl, + isIdxTyDecl, countTyClDecls, conDetailsTys, instDeclATs, @@ -52,6 +53,7 @@ import Outputable import Util ( count ) import SrcLoc ( Located(..), unLoc, noLoc ) import FastString +import Maybe ( isJust ) \end{code} @@ -329,6 +331,31 @@ Interface file code: -- for a module. That's why (despite the misnomer) IfaceSig and ForeignType -- are both in TyClDecl +-- Representation of indexed types +-- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ +-- Kind signatures of indexed types come in two flavours: +-- +-- * kind signatures for type functions: variant `TyFunction' and +-- +-- * kind signatures for indexed data types and newtypes : variant `TyData' +-- iff a kind is present in `tcdKindSig' and there are no constructors in +-- `tcdCons'. +-- +-- Indexed types are represented by 'TyData' and 'TySynonym' using the field +-- 'tcdTyPats::Maybe [LHsType name]', with the following meaning: +-- +-- * If it is 'Nothing', we have a *vanilla* data type declaration or type +-- synonym declaration and 'tcdVars' contains the type parameters of the +-- type constructor. +-- +-- * If it is 'Just pats', we have the definition of an indexed type Then, +-- 'pats' are type patterns for the type-indexes of the type constructor +-- and 'tcdVars' are the variables in those patterns. Hence, the arity of +-- the indexed type (ie, the number of indexes) is 'length tcdTyPats' and +-- *not* 'length tcdVars'. +-- +-- In both cases, 'tcdVars' collects all variables we need to quantify over. + type LTyClDecl name = Located (TyClDecl name) data TyClDecl name @@ -344,7 +371,9 @@ data TyClDecl name tcdTyVars :: [LHsTyVarBndr name], -- Type variables tcdTyPats :: Maybe [LHsType name], -- Type patterns tcdKindSig:: Maybe Kind, -- Optional kind sig; - -- (only for the 'where' form) + -- (only for the + -- 'where' form and + -- indexed type sigs) tcdCons :: [LConDecl name], -- Data constructors -- For data T a = T1 | T2 a the LConDecls all have ResTyH98 @@ -359,8 +388,17 @@ data TyClDecl name -- are non-empty for the newtype-deriving case } + | TyFunction {tcdLName :: Located name, -- type constructor + tcdTyVars :: [LHsTyVarBndr name], -- type variables + tcdIso :: Bool, -- injective type? + tcdKind :: Kind -- result kind + } + | TySynonym { tcdLName :: Located name, -- type constructor tcdTyVars :: [LHsTyVarBndr name], -- type variables + tcdTyPats :: Maybe [LHsType name], -- Type patterns + -- 'Nothing' => vanilla + -- type synonym tcdSynRhs :: LHsType name -- synonym expansion } @@ -371,7 +409,8 @@ data TyClDecl name tcdSigs :: [LSig name], -- Methods' signatures tcdMeths :: LHsBinds name, -- Default methods tcdATs :: [LTyClDecl name] -- Associated types; ie - -- only 'TyData' + -- only 'TyData', + -- 'TyFunction', -- and 'TySynonym' } @@ -384,16 +423,35 @@ data NewOrData Simple classifiers \begin{code} -isDataDecl, isSynDecl, isClassDecl :: TyClDecl name -> Bool +isTFunDecl, isDataDecl, isSynDecl, isClassDecl, isKindSigDecl, isIdxTyDecl :: + TyClDecl name -> Bool + +-- type function kind signature +isTFunDecl (TyFunction {}) = True +isTFunDecl other = False -isSynDecl (TySynonym {}) = True -isSynDecl other = False +-- vanilla Haskell type synonym +isSynDecl (TySynonym {tcdTyPats = Nothing}) = True +isSynDecl other = False + +-- type equation (of a type function) +isTEqnDecl (TySynonym {tcdTyPats = Just _}) = True +isTEqnDecl other = False isDataDecl (TyData {}) = True isDataDecl other = False isClassDecl (ClassDecl {}) = True isClassDecl other = False + +-- kind signature (for an indexed type) +isKindSigDecl (TyFunction {} ) = True +isKindSigDecl (TyData {tcdKindSig = Just _, + tcdCons = [] }) = True +isKindSigDecl other = False + +-- definition of an instance of an indexed type +isIdxTyDecl = isJust . tcdTyPats \end{code} Dealing with names @@ -408,8 +466,11 @@ tyClDeclNames :: Eq name => TyClDecl name -> [Located name] -- For record fields, the first one counts as the SrcLoc -- We use the equality to filter out duplicate field names -tyClDeclNames (TySynonym {tcdLName = name}) = [name] -tyClDeclNames (ForeignType {tcdLName = name}) = [name] +tyClDeclNames (TyFunction {tcdLName = name}) = [name] +tyClDeclNames (TySynonym {tcdLName = name, + tcdTyPats= Nothing}) = [name] +tyClDeclNames (TySynonym {} ) = [] -- type equation +tyClDeclNames (ForeignType {tcdLName = name}) = [name] tyClDeclNames (ClassDecl {tcdLName = cls_name, tcdSigs = sigs, tcdATs = ats}) = cls_name : @@ -418,18 +479,22 @@ tyClDeclNames (ClassDecl {tcdLName = cls_name, tcdSigs = sigs, tcdATs = ats}) tyClDeclNames (TyData {tcdLName = tc_name, tcdCons = cons}) = tc_name : conDeclsNames (map unLoc cons) -tyClDeclTyVars (TySynonym {tcdTyVars = tvs}) = tvs -tyClDeclTyVars (TyData {tcdTyVars = tvs}) = tvs -tyClDeclTyVars (ClassDecl {tcdTyVars = tvs}) = tvs -tyClDeclTyVars (ForeignType {}) = [] +tyClDeclTyVars (TyFunction {tcdTyVars = tvs}) = tvs +tyClDeclTyVars (TySynonym {tcdTyVars = tvs}) = tvs +tyClDeclTyVars (TyData {tcdTyVars = tvs}) = tvs +tyClDeclTyVars (ClassDecl {tcdTyVars = tvs}) = tvs +tyClDeclTyVars (ForeignType {}) = [] \end{code} \begin{code} -countTyClDecls :: [TyClDecl name] -> (Int, Int, Int, Int) - -- class, data, newtype, synonym decls +countTyClDecls :: [TyClDecl name] -> (Int, Int, Int, Int, Int, Int) + -- class, synonym decls, type function signatures, + -- type function equations, data, newtype countTyClDecls decls = (count isClassDecl decls, count isSynDecl decls, + count isTFunDecl decls, + count isTEqnDecl decls, count isDataTy decls, count isNewTy decls) where @@ -447,8 +512,19 @@ instance OutputableBndr name ppr (ForeignType {tcdLName = ltycon}) = hsep [ptext SLIT("foreign import type dotnet"), ppr ltycon] - ppr (TySynonym {tcdLName = ltycon, tcdTyVars = tyvars, tcdSynRhs = mono_ty}) - = hang (ptext SLIT("type") <+> pp_decl_head [] ltycon tyvars Nothing <+> equals) + ppr (TyFunction {tcdLName = ltycon, tcdTyVars = tyvars, tcdIso = iso, + tcdKind = kind}) + = typeMaybeIso <+> pp_decl_head [] ltycon tyvars Nothing <+> + dcolon <+> pprKind kind + where + typeMaybeIso = if iso + then ptext SLIT("type iso") + else ptext SLIT("type") + + ppr (TySynonym {tcdLName = ltycon, tcdTyVars = tyvars, tcdTyPats = typats, + tcdSynRhs = mono_ty}) + = hang (ptext SLIT("type") <+> pp_decl_head [] ltycon tyvars typats <+> + equals) 4 (ppr mono_ty) ppr (TyData {tcdND = new_or_data, tcdCtxt = context, tcdLName = ltycon, @@ -615,7 +691,8 @@ data InstDecl name -- figures out the quantified type variables for us. (LHsBinds name) [LSig name] -- User-supplied pragmatic info - [LTyClDecl name]-- Associated types + [LTyClDecl name]-- Associated types (ie, 'TyData' and + -- 'TySynonym' only) instance (OutputableBndr name) => Outputable (InstDecl name) where