Files
gf-core/src/GF/CF/CFIdent.hs
2004-05-26 18:44:40 +00:00

179 lines
4.3 KiB
Haskell

module CFIdent where
import Operations
import GFC
import Ident
import Values (cPredefAbs)
import AbsGFC
import Macros (ident2label)
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 m -> m --- "?" --- m
-- to build trees: the Atom contains a GF function, Cn | Meta | Vr | Literal
newtype CFFun = CFFun (Atom, Profile) deriving (Eq,Ord,Show)
-- - - - - - - - - - - - - - - - - - - - - ^^^ added by peb, 21/5-04
type Profile = [([[Int]],[Int])]
wordsCFTok :: CFTok -> [String]
wordsCFTok t = case t of
TC (c:cs) -> [c':cs | c' <- [toUpper c, toLower c]]
_ -> [prCFTok t]
-- the following functions should be used instead of constructors
-- to construct CF functions
mkCFFun :: Atom -> CFFun
mkCFFun t = CFFun (t,[])
varCFFun :: Ident -> CFFun
varCFFun = mkCFFun . AV
consCFFun :: CIdent -> CFFun
consCFFun = mkCFFun . AC
-- standard way of making cf fun
string2CFFun :: String -> String -> CFFun
string2CFFun m c = consCFFun $ mkCIdent m c
stringCFFun :: String -> CFFun
stringCFFun = mkCFFun . AS
intCFFun :: Int -> CFFun
intCFFun = mkCFFun . AI . toInteger
dummyCFFun :: CFFun
dummyCFFun = varCFFun $ identC "_" --- used in lexer-by-need rules
cfFun2String :: CFFun -> String
cfFun2String (CFFun (f,_)) = prt f
cfFun2Ident :: CFFun -> Ident
cfFun2Ident (CFFun (f,_)) = identC $ 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 "_") ----
cat2CFCat :: (Ident,Ident) -> CFCat
cat2CFCat = uncurry idents2CFCat
---- literals
cfCatString = string2CFCat (prt cPredefAbs) "String"
cfCatInt = string2CFCat (prt cPredefAbs) "Int"
{- ----
uCFCat :: CFCat
uCFCat = cat2CFCat uCat
-}
moduleOfCFCat :: CFCat -> Ident
moduleOfCFCat (CFCat (CIQ m _, _)) = m
-- the opposite direction
cfCat2Cat :: CFCat -> (Ident,Ident)
cfCat2Cat (CFCat (CIQ m c,_)) = (m,c)
cfCat2Ident :: CFCat -> Ident
cfCat2Ident = snd . cfCat2Cat
lexCFCat :: CFCat -> CFCat
lexCFCat cat = ident2CFCat (uncurry CIQ (cfCat2Cat cat)) (identC "*")
-- 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 (TM _ _) _ = True --- hack because metas are renamed
compatTok _ (TM _ _) = True
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'