reorganize the modules in GF.Compile.*

src/compiler/GF/Compile/Compute/AppPredefined.hs

@@ -0,0 +1,157 @@
+----------------------------------------------------------------------
+-- |
+-- Module      : AppPredefined
+-- Maintainer  : AR
+-- Stability   : (stable)
+-- Portability : (portable)
+--
+-- > CVS $Date: 2005/10/06 14:21:34 $ 
+-- > CVS $Author: aarne $
+-- > CVS $Revision: 1.13 $
+--
+-- Predefined function type signatures and definitions.
+-----------------------------------------------------------------------------
+
+module GF.Compile.Compute.AppPredefined (isInPredefined, typPredefined, appPredefined
+		     ) where
+
+import GF.Infra.Ident
+import GF.Data.Operations
+import GF.Grammar.Predef
+import GF.Grammar.Grammar
+import GF.Grammar.Macros
+import GF.Grammar.Printer
+import qualified Data.ByteString.Char8 as BS
+import Text.PrettyPrint
+
+-- predefined function type signatures and definitions. AR 12/3/2003.
+
+isInPredefined :: Ident -> Bool
+isInPredefined = err (const True) (const False) . typPredefined
+
+typPredefined :: Ident -> Err Type
+typPredefined f
+  | f == cInt       = return typePType
+  | f == cFloat     = return typePType
+  | f == cErrorType = return typeType
+  | f == cInts      = return $ mkFunType [typeInt] typePType
+  | f == cPBool     = return typePType
+  | f == cError     = return $ mkFunType [typeStr] typeError  -- non-can. of empty set
+  | f == cPFalse    = return $ typePBool
+  | f == cPTrue     = return $ typePBool
+  | f == cDp        = return $ mkFunType [typeInt,typeTok] typeTok
+  | f == cDrop      = return $ mkFunType [typeInt,typeTok] typeTok
+  | f == cEqInt     = return $ mkFunType [typeInt,typeInt] typePBool
+  | f == cLessInt   = return $ mkFunType [typeInt,typeInt] typePBool
+  | f == cEqStr     = return $ mkFunType [typeTok,typeTok] typePBool
+  | f == cLength    = return $ mkFunType [typeTok] typeInt
+  | f == cOccur     = return $ mkFunType [typeTok,typeTok] typePBool
+  | f == cOccurs    = return $ mkFunType [typeTok,typeTok] typePBool
+  | f == cPlus      = return $ mkFunType [typeInt,typeInt] (typeInt)
+----  "read"   -> (P : Type) -> Tok -> P
+  | f == cShow      = return $ mkProd -- (P : PType) -> P -> Tok
+    [(Explicit,varP,typePType),(Explicit,identW,Vr varP)] typeStr []
+  | f == cToStr     = return $ mkProd -- (L : Type)  -> L -> Str
+    [(Explicit,varL,typeType),(Explicit,identW,Vr varL)] typeStr []
+  | f == cMapStr    = return $ mkProd -- (L : Type)  -> (Str -> Str) -> L -> L
+    [(Explicit,varL,typeType),(Explicit,identW,mkFunType [typeStr] typeStr),(Explicit,identW,Vr varL)] (Vr varL) []
+  | f == cTake      = return $ mkFunType [typeInt,typeTok] typeTok
+  | f == cTk        = return $ mkFunType [typeInt,typeTok] typeTok
+  | otherwise       = Bad (render (text "unknown in Predef:" <+> ppIdent f))
+
+varL :: Ident
+varL = identC (BS.pack "L")
+
+varP :: Ident
+varP = identC (BS.pack "P")
+
+appPredefined :: Term -> Err (Term,Bool)
+appPredefined t = case t of
+  App f x0 -> do
+   (x,_) <- appPredefined x0
+   case f of
+    -- one-place functions
+    Q (mod,f) | mod == cPredef ->
+      case x of
+        (K s) | f == cLength -> retb $ EInt $ length s
+        _                    -> retb t
+
+    -- two-place functions
+    App (Q (mod,f)) z0 | mod == cPredef -> do
+     (z,_) <- appPredefined z0
+     case (norm z, norm x) of
+      (EInt i, K s)    | f == cDrop    -> retb $ K (drop i s)
+      (EInt i, K s)    | f == cTake    -> retb $ K (take i s)
+      (EInt i, K s)    | f == cTk      -> retb $ K (take (max 0 (length s - i)) s)
+      (EInt i, K s)    | f == cDp      -> retb $ K (drop (max 0 (length s - i)) s)
+      (K s,    K t)    | f == cEqStr   -> retb $ if s == t then predefTrue else predefFalse
+      (K s,    K t)    | f == cOccur   -> retb $ if substring s t then predefTrue else predefFalse
+      (K s,    K t)    | f == cOccurs  -> retb $ if any (flip elem t) s then predefTrue else predefFalse
+      (EInt i, EInt j) | f == cEqInt   -> retb $ if i==j then predefTrue else predefFalse
+      (EInt i, EInt j) | f == cLessInt -> retb $ if i<j  then predefTrue else predefFalse
+      (EInt i, EInt j) | f == cPlus    -> retb $ EInt $ i+j
+      (_,      t)      | f == cShow    -> retb $ foldr C Empty $ map K $ words $ render (ppTerm Unqualified 0 t)
+      (_,      K s)    | f == cRead    -> retb $ Cn (identC (BS.pack s)) --- because of K, only works for atomic tags
+      (_,      t)      | f == cToStr   -> trm2str t >>= retb
+      _ -> retb t ---- prtBad "cannot compute predefined" t
+
+    -- three-place functions
+    App (App (Q (mod,f)) z0) y0 | mod == cPredef -> do
+     (y,_) <- appPredefined y0
+     (z,_) <- appPredefined z0
+     case (z, y, x) of
+       (ty,op,t) | f == cMapStr -> retf $ mapStr ty op t
+       _ -> retb t ---- prtBad "cannot compute predefined" t
+
+    _ -> retb t ---- prtBad "cannot compute predefined" t
+  _ -> retb t
+                  ---- should really check the absence of arg variables
+ where
+   retb t = return (retc t,True)  -- no further computing needed
+   retf t = return (retc t,False) -- must be computed further
+   retc t = case t of
+     K [] -> t
+     K s  -> foldr1 C (map K (words s))
+     _    -> t
+   norm t = case t of
+     Empty -> K []
+     C u v -> case (norm u,norm v) of
+       (K x,K y) -> K (x +++ y)
+       _ -> t
+     _ -> t
+
+-- read makes variables into constants
+
+predefTrue = QC (cPredef,cPTrue)
+predefFalse = QC (cPredef,cPFalse)
+
+substring :: String -> String -> Bool
+substring s t = case (s,t) of
+  (c:cs, d:ds) -> (c == d && substring cs ds) || substring s ds
+  ([],_) -> True
+  _ -> False
+
+trm2str :: Term -> Err Term
+trm2str t = case t of
+  R ((_,(_,s)):_) -> trm2str s
+  T _ ((_,s):_)   -> trm2str s
+  V _ (s:_)       -> trm2str s
+  C _ _           -> return $ t
+  K _             -> return $ t
+  S c _           -> trm2str c
+  Empty           -> return $ t
+  _               -> Bad (render (text "cannot get Str from term" <+> ppTerm Unqualified 0 t))
+
+-- simultaneous recursion on type and term: type arg is essential!
+-- But simplify the task by assuming records are type-annotated
+-- (this has been done in type checking)
+mapStr :: Type -> Term -> Term -> Term
+mapStr ty f t = case (ty,t) of
+  _ | elem ty [typeStr,typeTok] -> App f t
+  (_,        R ts)    -> R [(l,mapField v)   | (l,v) <- ts]
+  (Table a b,T ti cs) -> T ti [(p,mapStr b f v) | (p,v) <- cs]
+  _    -> t 
+ where
+   mapField (mty,te) = case mty of
+     Just ty -> (mty,mapStr ty f te)
+     _ -> (mty,te)