Files
gf-core/src-3.0/GF/GFCC/API.hs

185 lines
5.9 KiB
Haskell

----------------------------------------------------------------------
-- |
-- Module : GFCCAPI
-- Maintainer : Aarne Ranta
-- Stability : (stable)
-- Portability : (portable)
--
-- > CVS $Date:
-- > CVS $Author:
-- > CVS $Revision:
--
-- Reduced Application Programmer's Interface to GF, meant for
-- embedded GF systems. AR 19/9/2007
-----------------------------------------------------------------------------
module GF.GFCC.API where
import GF.GFCC.Linearize
import GF.GFCC.Generate
import GF.GFCC.Macros
import GF.GFCC.DataGFCC
import GF.GFCC.CId
import GF.GFCC.Raw.ConvertGFCC
import GF.GFCC.Raw.ParGFCCRaw
import GF.Data.ErrM
import GF.GFCC.Parsing.FCFG
import Data.Char
import qualified Data.Map as Map
import Control.Monad
import System.Random (newStdGen)
import System.Directory (doesFileExist)
import qualified Text.PrettyPrint as PP
import qualified Text.ParserCombinators.ReadP as RP
-- This API is meant to be used when embedding GF grammars in Haskell
-- programs. The embedded system is supposed to use the
-- .gfcc grammar format, which is first produced by the gf program.
---------------------------------------------------
-- Interface
---------------------------------------------------
data MultiGrammar = MultiGrammar {gfcc :: GFCC}
type Language = String
type Category = String
type Tree = Exp
file2grammar :: FilePath -> IO MultiGrammar
linearize :: MultiGrammar -> Language -> Tree -> String
parse :: MultiGrammar -> Language -> Category -> String -> [Tree]
linearizeAll :: MultiGrammar -> Tree -> [String]
linearizeAllLang :: MultiGrammar -> Tree -> [(Language,String)]
parseAll :: MultiGrammar -> Category -> String -> [[Tree]]
parseAllLang :: MultiGrammar -> Category -> String -> [(Language,[Tree])]
generateAll :: MultiGrammar -> Category -> [Tree]
generateRandom :: MultiGrammar -> Category -> IO [Tree]
generateAllDepth :: MultiGrammar -> Category -> Maybe Int -> [Tree]
readTree :: String -> Tree
showTree :: Tree -> String
languages :: MultiGrammar -> [Language]
categories :: MultiGrammar -> [Category]
startCat :: MultiGrammar -> Category
---------------------------------------------------
-- Implementation
---------------------------------------------------
file2grammar f = do
gfcc <- file2gfcc f
return (MultiGrammar gfcc)
file2gfcc f = do
s <- readFileIf f
g <- parseGrammar s
return $ toGFCC g
linearize mgr lang = GF.GFCC.Linearize.linearize (gfcc mgr) (mkCId lang)
parse mgr lang cat s =
case lookParser (gfcc mgr) (mkCId lang) of
Nothing -> error "no parser"
Just pinfo -> case parseFCF "bottomup" pinfo (mkCId cat) (words s) of
Ok x -> x
Bad s -> error s
linearizeAll mgr = map snd . linearizeAllLang mgr
linearizeAllLang mgr t =
[(lang,linearThis mgr lang t) | lang <- languages mgr]
parseAll mgr cat = map snd . parseAllLang mgr cat
parseAllLang mgr cat s =
[(lang,ts) | lang <- languages mgr, let ts = parse mgr lang cat s, not (null ts)]
generateRandom mgr cat = do
gen <- newStdGen
return $ genRandom gen (gfcc mgr) (mkCId cat)
generateAll mgr cat = generate (gfcc mgr) (mkCId cat) Nothing
generateAllDepth mgr cat = generate (gfcc mgr) (mkCId cat)
readTree s = case RP.readP_to_S (pExp 0) s of
[(x,"")] -> x
_ -> error "no parse"
pExps :: RP.ReadP [Exp]
pExps = liftM2 (:) (pExp 1) pExps RP.<++ (RP.skipSpaces >> return [])
pExp :: Int -> RP.ReadP Exp
pExp n = RP.skipSpaces >> (pParen RP.<++ pApp RP.<++ pNum RP.<++ pStr RP.<++ pMeta)
where
pParen = RP.between (RP.char '(') (RP.char ')') (pExp 0)
pApp = do xs <- RP.option [] (RP.between (RP.char '\\') (RP.string "->") (RP.sepBy1 pIdent (RP.char ',')))
f <- pIdent
ts <- (if n == 0 then pExps else return [])
return (DTr xs (AC f) ts)
pStr = RP.char '"' >> liftM (\s -> DTr [] (AS s) []) (RP.manyTill (pEsc RP.<++ RP.get) (RP.char '"'))
pEsc = RP.char '\\' >> RP.get
pNum = do x <- RP.munch1 isDigit
((RP.char '.' >> RP.munch1 isDigit >>= \y -> return (DTr [] (AF (read (x++"."++y))) []))
RP.<++
(return (DTr [] (AI (read x)) [])))
pMeta = do RP.char '?'
x <- RP.munch1 isDigit
return (DTr [] (AM (read x)) [])
pIdent = fmap mkCId (liftM2 (:) (RP.satisfy isIdentFirst) (RP.munch isIdentRest))
isIdentFirst c = c == '_' || isLetter c
isIdentRest c = c == '_' || c == '\'' || isAlphaNum c
showTree = PP.render . ppExp False
ppExp isNested (DTr [] at []) = ppAtom at
ppExp isNested (DTr xs at ts) = ppParens isNested (ppLambdas xs PP.<+> ppAtom at PP.<+> PP.hsep (map (ppExp True) ts))
where
ppLambdas [] = PP.empty
ppLambdas xs = PP.char '\\' PP.<>
PP.hsep (PP.punctuate PP.comma (map (PP.text . prCId) xs)) PP.<+>
PP.text "->"
ppParens True = PP.parens
ppParens False = id
ppAtom (AC id) = PP.text (prCId id)
ppAtom (AS s) = PP.text (show s)
ppAtom (AI n) = PP.integer n
ppAtom (AF d) = PP.double d
ppAtom (AM n) = PP.char '?' PP.<> PP.integer n
ppAtom (AV id) = PP.text (prCId id)
abstractName mgr = prCId (absname (gfcc mgr))
languages mgr = [prCId l | l <- cncnames (gfcc mgr)]
categories mgr = [prCId c | c <- Map.keys (cats (abstract (gfcc mgr)))]
startCat mgr = lookStartCat (gfcc mgr)
emptyMultiGrammar = MultiGrammar emptyGFCC
------------ for internal use only
linearThis = GF.GFCC.API.linearize
err f g ex = case ex of
Ok x -> g x
Bad s -> f s
readFileIf f = do
b <- doesFileExist f
if b then readFile f
else putStrLn ("file " ++ f ++ " not found") >> return ""