Founding the newly structured GF2.0 cvs archive.

src/GF/CF/CFIdent.hs

@@ -0,0 +1,151 @@
+module CFIdent where
+
+import Operations
+import GFC
+import Ident
+import AbsGFC
+import PrGrammar
+import Str
+import Char (toLower, toUpper)
+
+-- symbols (categories, functions) for context-free grammars.
+
+-- these types should be abstract
+
+data CFTok = 
+   TS String     -- normal strings
+ | TC String     -- strings that are ambiguous between upper or lower case
+ | TL String     -- string literals
+ | TI Int        -- integer literals
+ | TV Ident      -- variables
+ | TM Int String -- metavariables; the integer identifies it
+  deriving (Eq, Ord, Show)
+
+newtype CFCat = CFCat (CIdent,Label) deriving (Eq, Ord, Show)
+
+tS, tC, tL, tI, tV, tM :: String -> CFTok
+tS  = TS
+tC  = TC
+tL  = TL
+tI  = TI . read 
+tV  = TV . identC
+tM  = TM 0
+
+tInt :: Int -> CFTok
+tInt = TI
+
+prCFTok :: CFTok -> String
+prCFTok t = case t of
+  TS s -> s
+  TC s -> s
+  TL s -> s
+  TI i -> show i
+  TV x -> prt x
+  TM i _ -> "?" ---
+
+-- to build trees: the Atom contains a GF function, Cn | Meta | Vr | Literal
+newtype CFFun = CFFun (Atom, Profile) deriving (Eq,Show)
+
+type Profile  = [([[Int]],[Int])]
+
+
+-- the following functions should be used instead of constructors
+
+-- to construct CF functions
+
+mkCFFun :: Atom -> CFFun
+mkCFFun t = CFFun (t,[])
+
+{- ----
+getCFLiteral :: String -> Maybe (CFCat, CFFun)
+getCFLiteral s = case lookupLiteral' s of
+  Ok (c, lit) -> Just (cat2CFCat c, mkCFFun lit)
+  _ -> Nothing
+-}
+
+varCFFun :: Ident -> CFFun
+varCFFun = mkCFFun . AV
+
+consCFFun :: CIdent -> CFFun
+consCFFun = mkCFFun . AC
+
+{- ----
+string2CFFun :: String -> CFFun 
+string2CFFun = consCFFun . Ident
+-}
+
+cfFun2String :: CFFun -> String
+cfFun2String (CFFun (f,_)) = prt f
+
+cfFun2Profile :: CFFun -> Profile
+cfFun2Profile (CFFun (_,p)) = p
+
+{- ----
+strPro2cfFun :: String -> Profile -> CFFun
+strPro2cfFun str p = (CFFun (AC (Ident str), p))
+-}
+
+metaCFFun :: CFFun
+metaCFFun = mkCFFun $ AM 0
+
+-- to construct CF categories
+
+-- belongs elsewhere
+mkCIdent :: String -> String -> CIdent
+mkCIdent m c = CIQ (identC m) (identC c)
+
+ident2CFCat :: CIdent -> Ident -> CFCat
+ident2CFCat mc d = CFCat (mc, L d)
+
+-- standard way of making cf cat: label s
+string2CFCat :: String -> String -> CFCat
+string2CFCat m c = ident2CFCat (mkCIdent m c) (identC "s")
+
+idents2CFCat :: Ident -> Ident -> CFCat
+idents2CFCat m c = ident2CFCat (CIQ m c) (identC "s")
+
+catVarCF :: CFCat
+catVarCF = ident2CFCat (mkCIdent "_" "#Var") (identC "_") ----
+
+{- ----
+uCFCat :: CFCat
+uCFCat = cat2CFCat uCat
+-}
+
+moduleOfCFCat :: CFCat -> Ident
+moduleOfCFCat (CFCat (CIQ m _, _)) = m
+
+-- the opposite direction
+cfCat2Cat :: CFCat -> CIdent   
+cfCat2Cat (CFCat (s,_)) = s
+
+
+-- to construct CF tokens
+
+string2CFTok :: String -> CFTok
+string2CFTok = tS
+
+str2cftoks :: Str -> [CFTok]
+str2cftoks = map tS . words . sstr
+
+-- decide if two token lists look the same (in parser postprocessing)
+
+compatToks :: [CFTok] -> [CFTok] -> Bool
+compatToks ts us = and [compatTok t u | (t,u) <- zip ts us]
+
+compatTok t u = any (`elem` (alts t)) (alts u) where
+  alts u = case u of
+    TC (c:s) -> [toLower c : s, toUpper c : s]
+    _ -> [prCFTok u]
+
+-- decide if two CFFuns have the same function head (profiles may differ)
+
+compatCFFun :: CFFun -> CFFun -> Bool
+compatCFFun (CFFun (f,_)) (CFFun (g,_)) = f == g
+
+-- decide whether two categories match
+-- the modifiers can be from different modules, but on the same extension
+-- path, so there is no clash, and they can be safely ignored ---
+compatCF :: CFCat -> CFCat -> Bool
+----compatCF = (==)
+compatCF (CFCat (CIQ _ c, l)) (CFCat (CIQ _ c', l')) = c==c' && l==l'