Add external data declarations

src/Curry/Syntax/Parser.hs

@@ -237,13 +237,18 @@ topDecls :: Parser a Token [Decl ()]
 topDecls = topDecl `sepBy` semicolon
 
 topDecl :: Parser a Token (Decl ())
-topDecl = choice [ dataDecl, newtypeDecl, typeDecl, classDecl, instanceDecl
-                 , defaultDecl, foreignDecl, infixDecl, functionDecl ]
+topDecl = choice [ dataDecl, externalDataDecl, newtypeDecl, typeDecl
+                 , classDecl, instanceDecl, defaultDecl
+                 , foreignDecl, infixDecl, functionDecl ]
 
 dataDecl :: Parser a Token (Decl ())
 dataDecl = typeDeclLhs DataDecl KW_data <*> constrs <*> deriv
   where constrs = equals <-*> constrDecl `sepBy1` bar `opt` []
 
+externalDataDecl :: Parser a Token (Decl ())
+externalDataDecl = decl <$> tokenPos KW_external <*> typeDeclLhs (,,) KW_data
+  where decl p (_, tc, tvs) = ExternalDataDecl p tc tvs
+
 newtypeDecl :: Parser a Token (Decl ())
 newtypeDecl = typeDeclLhs NewtypeDecl KW_newtype <*-> equals <*> newConstrDecl
                                                              <*> deriv

src/Curry/Syntax/Pretty.hs

@@ -92,10 +92,11 @@ ppSepBlock = vcat . map (\d -> text "" $+$ ppDecl d)
 -- |Pretty print a declaration
 ppDecl :: Decl a -> Doc
 ppDecl (InfixDecl _ fix p ops) = ppPrec fix p <+> list (map ppInfixOp ops)
-ppDecl (DataDecl  _ tc tvs cs clss) =
+ppDecl (DataDecl _ tc tvs cs clss) =
   sep (ppTypeDeclLhs "data" tc tvs :
        map indent (zipWith (<+>) (equals : repeat vbar) (map ppConstr cs) ++
                    [ppDeriving clss]))
+ppDecl (ExternalDataDecl _ tc tvs) = ppTypeDeclLhs "external data" tc tvs
 ppDecl (NewtypeDecl _ tc tvs nc clss) =
   sep (ppTypeDeclLhs "newtype" tc tvs <+> equals :
        map indent [ppNewConstr nc, ppDeriving clss])

src/Curry/Syntax/ShowModule.hs

@@ -138,6 +138,12 @@ showsDecl (DataDecl pos ident idents consdecls classes)
   . showsList showsConsDecl consdecls . space
   . showsList showsQualIdent classes
   . showsString ")"
+showsDecl (ExternalDataDecl pos ident idents)
+  = showsString "(ExternalDataDecl "
+  . showsPosition pos . space
+  . showsIdent ident . space
+  . showsList showsIdent idents
+  . showsString ")"
 showsDecl (NewtypeDecl pos ident idents newconsdecl classes)
   = showsString "(NewtypeDecl "
   . showsPosition pos . space

src/Curry/Syntax/Type.hs

@@ -149,19 +149,20 @@ data KindExpr
 
 -- |Declaration in a module
 data Decl a
-  = InfixDecl    Position Infix (Maybe Precedence) [Ident]         -- infixl 5 (op), `fun`
-  | DataDecl     Position Ident [Ident] [ConstrDecl] [QualIdent]   -- data C a b = C1 a | C2 b deriving (D, ...)
-  | NewtypeDecl  Position Ident [Ident] NewConstrDecl [QualIdent]  -- newtype C a b = C a b deriving (D, ...)
-  | TypeDecl     Position Ident [Ident] TypeExpr                   -- type C a b = D a b
-  | TypeSig      Position [Ident] QualTypeExpr                     -- f, g :: Bool
-  | FunctionDecl Position a Ident [Equation a]                     -- f True = 1 ; f False = 0
-  | ForeignDecl  Position CallConv (Maybe String) a Ident TypeExpr -- foreign ccall "lib.h" fun :: Int
-  | ExternalDecl Position [Var a]                                  -- f, g external
-  | PatternDecl  Position (Pattern a) (Rhs a)                      -- Just x = ...
-  | FreeDecl     Position [Var a]                                  -- x, y free
-  | DefaultDecl  Position [TypeExpr]                               -- default (Int, Float)
-  | ClassDecl    Position Context Ident Ident [Decl a]             -- class C a => D a where {TypeSig|InfixDecl|FunctionDecl}
-  | InstanceDecl Position Context QualIdent InstanceType [Decl a]  -- instance C a => M.D (N.T a b c) where {FunctionDecl}
+  = InfixDecl        Position Infix (Maybe Precedence) [Ident]         -- infixl 5 (op), `fun`
+  | DataDecl         Position Ident [Ident] [ConstrDecl] [QualIdent]   -- data C a b = C1 a | C2 b deriving (D, ...)
+  | ExternalDataDecl Position Ident [Ident]
+  | NewtypeDecl      Position Ident [Ident] NewConstrDecl [QualIdent]  -- newtype C a b = C a b deriving (D, ...)
+  | TypeDecl         Position Ident [Ident] TypeExpr                   -- type C a b = D a b
+  | TypeSig          Position [Ident] QualTypeExpr                     -- f, g :: Bool
+  | FunctionDecl     Position a Ident [Equation a]                     -- f True = 1 ; f False = 0
+  | ForeignDecl      Position CallConv (Maybe String) a Ident TypeExpr -- foreign ccall "lib.h" fun :: Int
+  | ExternalDecl     Position [Var a]                                  -- f, g external
+  | PatternDecl      Position (Pattern a) (Rhs a)                      -- Just x = ...
+  | FreeDecl         Position [Var a]                                  -- x, y free
+  | DefaultDecl      Position [TypeExpr]                               -- default (Int, Float)
+  | ClassDecl        Position Context Ident Ident [Decl a]             -- class C a => D a where {TypeSig|InfixDecl|FunctionDecl}
+  | InstanceDecl     Position Context QualIdent InstanceType [Decl a]  -- instance C a => M.D (N.T a b c) where {FunctionDecl}
     deriving (Eq, Read, Show)
 
 -- ---------------------------------------------------------------------------
@@ -355,6 +356,7 @@ instance Functor Module where
 instance Functor Decl where
   fmap _ (InfixDecl p fix prec ops) = InfixDecl p fix prec ops
   fmap _ (DataDecl p tc tvs cs clss) = DataDecl p tc tvs cs clss
+  fmap _ (ExternalDataDecl p tc tvs) = ExternalDataDecl p tc tvs
   fmap _ (NewtypeDecl p tc tvs nc clss) = NewtypeDecl p tc tvs nc clss
   fmap _ (TypeDecl p tc tvs ty) = TypeDecl p tc tvs ty
   fmap _ (TypeSig p fs qty) = TypeSig p fs qty

src/Curry/Syntax/Utils.hs

@@ -74,10 +74,11 @@ isInfixDecl _                   = False
 
 -- |Is the declaration a type declaration?
 isTypeDecl :: Decl a -> Bool
-isTypeDecl (DataDecl    _ _ _ _ _) = True
-isTypeDecl (NewtypeDecl _ _ _ _ _) = True
-isTypeDecl (TypeDecl      _ _ _ _) = True
-isTypeDecl _                       = False
+isTypeDecl (DataDecl     _ _ _ _ _) = True
+isTypeDecl (ExternalDataDecl _ _ _) = True
+isTypeDecl (NewtypeDecl  _ _ _ _ _) = True
+isTypeDecl (TypeDecl       _ _ _ _) = True
+isTypeDecl _                        = False
 
 -- |Is the declaration a default declaration?
 isDefaultDecl :: Decl a -> Bool