oops - forgot to add GFCCtoHaskell

1 files changed, 214 insertions, 0 deletions

diff --git a/src/GF/Devel/GFCCtoHaskell.hs b/src/GF/Devel/GFCCtoHaskell.hs
new file mode 100644
index 000000000..3c1382438
--- /dev/null
+++ b/src/GF/Devel/GFCCtoHaskell.hs
@@ -0,0 +1,214 @@
+----------------------------------------------------------------------
+-- |
+-- Module      : GFCCtoHaskell
+-- Maintainer  : Aarne Ranta
+-- Stability   : (stable)
+-- Portability : (portable)
+--
+-- > CVS $Date: 2005/06/17 12:39:07 $ 
+-- > CVS $Author: bringert $
+-- > CVS $Revision: 1.8 $
+--
+-- to write a GF abstract grammar into a Haskell module with translations from
+-- data objects into GF trees. Example: GSyntax for Agda.
+-- AR 11/11/1999 -- 7/12/2000 -- 18/5/2004
+-----------------------------------------------------------------------------
+
+module GF.Devel.GFCCtoHaskell (grammar2haskell, grammar2haskellGADT) where
+
+import GF.GFCC.Macros
+import GF.GFCC.DataGFCC
+import GF.GFCC.AbsGFCC
+
+import GF.Data.Operations
+
+import Data.List --(isPrefixOf, find, intersperse)
+import qualified Data.Map as Map
+
+-- | the main function
+grammar2haskell :: GFCC -> String
+grammar2haskell gr = foldr (++++) [] $  
+  haskPreamble ++ [datatypes gr', gfinstances gr', fginstances gr']
+    where gr' = hSkeleton gr
+
+grammar2haskellGADT :: GFCC -> String
+grammar2haskellGADT gr = foldr (++++) [] $  
+  ["{-# OPTIONS_GHC -fglasgow-exts #-}"] ++ 
+  haskPreamble ++ [datatypesGADT gr', gfinstances gr', fginstances gr']
+    where gr' = hSkeleton gr
+
+-- | by this you can prefix all identifiers with stg; the default is 'G'
+gId :: OIdent -> OIdent 
+gId i = 'G':i
+
+haskPreamble =
+ [
+  "module GSyntax where",
+  "",
+  "import GF.GFCC.DataGFCC",
+  "import GF.GFCC.AbsGFCC",
+  "----------------------------------------------------",
+  "-- automatic translation from GF to Haskell",
+  "----------------------------------------------------",
+  "", 
+  "class Gf a where gf :: a -> Exp",
+  "class Fg a where fg :: Exp -> a",
+  "",
+  predefInst "GString" "String" "DTr [] (AS s) []",
+  "",
+  predefInst "GInt" "Integer" "DTr [] (AI s) []",
+  "",
+  predefInst "GFloat" "Double" "DTr [] (AF s) []",
+  "",
+  "----------------------------------------------------",
+  "-- below this line machine-generated",
+  "----------------------------------------------------",
+  ""
+ ]
+
+predefInst gtyp typ patt = 
+  "newtype" +++ gtyp +++ "=" +++ gtyp +++ typ +++ " deriving Show" +++++
+  "instance Gf" +++ gtyp +++ "where" ++++
+  "  gf (" ++ gtyp +++ "s) =" +++ patt +++++
+  "instance Fg" +++ gtyp +++ "where" ++++
+  "  fg t =" ++++
+  "    case t of" ++++
+  "     " +++ patt +++ " ->" +++ gtyp +++ "s" ++++
+  "      _ -> error (\"no" +++ gtyp +++ "\" ++ show t)"
+
+type OIdent = String
+
+type HSkeleton = [(OIdent, [(OIdent, [OIdent])])]
+
+datatypes, gfinstances, fginstances :: (String,HSkeleton) -> String
+datatypes   = (foldr (+++++) "") . (filter (/="")) . (map hDatatype) . snd
+gfinstances (m,g) = (foldr (+++++) "") $ (filter (/="")) $ (map (hInstance m)) g
+fginstances (m,g) = (foldr (+++++) "") $ (filter (/="")) $ (map (fInstance m)) g
+
+hDatatype :: (OIdent, [(OIdent, [OIdent])]) -> String
+hInstance, fInstance :: String -> (OIdent, [(OIdent, [OIdent])]) -> String
+
+hDatatype ("Cn",_) = "" ---
+hDatatype (cat,[]) = ""
+hDatatype (cat,rules) | isListCat (cat,rules) = 
+ "newtype" +++ gId cat +++ "=" +++ gId cat +++ "[" ++ gId (elemCat cat) ++ "]" 
+  +++ "deriving Show"
+hDatatype (cat,rules) =
+ "data" +++ gId cat +++ "=" ++
+ (if length rules == 1 then "" else "\n  ") +++
+ foldr1 (\x y -> x ++ "\n |" +++ y) 
+        [gId f +++ foldr (+++) "" (map gId xx) | (f,xx) <- rules] ++++
+ "  deriving Show"
+
+-- GADT version of data types
+datatypesGADT :: (String,HSkeleton) -> String
+datatypesGADT (_,skel) = 
+    unlines (concatMap hCatTypeGADT skel)
+    +++++
+    "data Tree :: * -> * where" ++++ unlines (concatMap (map ("  "++) . hDatatypeGADT) skel)
+
+hCatTypeGADT :: (OIdent, [(OIdent, [OIdent])]) -> [String]
+hCatTypeGADT (cat,rules)
+    = ["type"+++gId cat+++"="+++"Tree"+++gId cat++"_",
+       "data"+++gId cat++"_"]
+
+hDatatypeGADT :: (OIdent, [(OIdent, [OIdent])]) -> [String]
+hDatatypeGADT (cat, rules) 
+    | isListCat (cat,rules) = [gId cat+++"::"+++"["++gId (elemCat cat)++"]" +++ "->" +++ t]
+    | otherwise =
+        [ gId f +++ "::" +++ concatMap (\a -> gId a +++ "-> ") args ++ t | (f,args) <- rules ]
+  where t = "Tree" +++ gId cat ++ "_"
+
+
+----hInstance m ("Cn",_) = "" --- seems to belong to an old applic. AR 18/5/2004
+hInstance m (cat,[]) = "" 
+hInstance m (cat,rules) 
+ | isListCat (cat,rules) =
+  "instance Gf" +++ gId cat +++ "where" ++++
+     " gf (" ++ gId cat +++ "[" ++ concat (intersperse "," baseVars) ++ "])" 
+           +++ "=" +++ mkRHS ("Base"++ec) baseVars ++++
+     " gf (" ++ gId cat +++ "(x:xs)) = " 
+           ++ mkRHS ("Cons"++ec) ["x",prParenth (gId cat+++"xs")] 
+-- no show for GADTs
+--     ++++ " gf (" ++ gId cat +++ "xs) = error (\"Bad " ++ cat ++ " value: \" ++ show xs)" 
+ | otherwise =
+  "instance Gf" +++ gId cat +++ "where" ++
+  (if length rules == 1 then "" else "\n") +++
+  foldr1 (\x y -> x ++ "\n" +++ y) [mkInst f xx | (f,xx) <- rules]
+ where
+   ec = elemCat cat
+   baseVars = mkVars (baseSize (cat,rules))
+   mkInst f xx = let xx' = mkVars (length xx) in "gf " ++
+     (if length xx == 0 then gId f else prParenth (gId f +++ foldr1 (+++) xx')) +++
+     "=" +++ mkRHS f xx'
+   mkVars n = ["x" ++ show i | i <- [1..n]]
+   mkRHS f vars = "DTr [] (AC (CId \"" ++ f ++ "\"))" +++ 
+		   "[" ++ prTList ", " ["gf" +++ x | x <- vars] ++ "]"
+
+
+----fInstance m ("Cn",_) = "" ---
+fInstance m (cat,[]) = ""
+fInstance m (cat,rules) =
+  "instance Fg" +++ gId cat +++ "where" ++++
+  " fg t =" ++++
+  "  case t of" ++++
+  foldr1 (\x y -> x ++ "\n" ++ y) [mkInst f xx | (f,xx) <- rules] ++++
+  "    _ -> error (\"no" +++ cat ++ " \" ++ show t)"
+   where
+    mkInst f xx =
+     "    DTr [] (AC (CId \"" ++ f ++ "\")) " ++
+     "[" ++ prTList "," xx' ++ "]" +++
+     "->" +++ mkRHS f xx'
+       where xx' = ["x" ++ show i | (_,i) <- zip xx [1..]]
+	     mkRHS f vars 
+		 | isListCat (cat,rules) =
+		     if "Base" `isPrefixOf` f then
+			gId cat +++ "[" ++ prTList ", " [ "fg" +++ x | x <- vars ] ++ "]"
+		      else
+                       let (i,t) = (init vars,last vars)
+                        in "let" +++ gId cat +++ "xs = fg " ++ t +++ "in" +++ 
+                          gId cat +++ prParenth (prTList ":" (["fg"+++v | v <- i] ++ ["xs"]))
+		 | otherwise = 
+		     gId f +++  
+		     prTList " " [prParenth ("fg" +++ x) | x <- vars]
+
+
+--type HSkeleton = [(OIdent, [(OIdent, [OIdent])])]
+hSkeleton :: GFCC -> (String,HSkeleton)
+hSkeleton gr = 
+  (pr (absname gr), 
+   [(pr c, [(pr f, map pr cs) | (f, (cs,_)) <- fs]) | 
+                                        fs@((_, (_,c)):_) <- fns]
+  )
+ where
+   fns = groupBy valtypg (sortBy valtyps (map jty (Map.assocs (funs (abstract gr)))))
+   valtyps (_, (_,x)) (_, (_,y)) = compare x y
+   valtypg (_, (_,x)) (_, (_,y)) = x == y
+   pr (CId c) = c
+   jty (f,(ty,_)) = (f,catSkeleton ty)
+
+updateSkeleton :: OIdent -> HSkeleton -> (OIdent, [OIdent]) -> HSkeleton
+updateSkeleton cat skel rule =
+ case skel of
+   (cat0,rules):rr | cat0 == cat -> (cat0, rule:rules) : rr
+   (cat0,rules):rr               -> (cat0, rules) : updateSkeleton cat rr rule
+
+isListCat :: (OIdent, [(OIdent, [OIdent])]) -> Bool
+isListCat (cat,rules) = "List" `isPrefixOf` cat && length rules == 2
+		    && ("Base"++c) `elem` fs && ("Cons"++c) `elem` fs
+    where c = elemCat cat
+	  fs = map fst rules
+
+-- | Gets the element category of a list category.
+elemCat :: OIdent -> OIdent
+elemCat = drop 4
+
+isBaseFun :: OIdent -> Bool
+isBaseFun f = "Base" `isPrefixOf` f
+
+isConsFun :: OIdent -> Bool
+isConsFun f = "Cons" `isPrefixOf` f
+
+baseSize :: (OIdent, [(OIdent, [OIdent])]) -> Int
+baseSize (_,rules) = length bs
+    where Just (_,bs) = find (("Base" `isPrefixOf`) . fst) rules