Files
gf-core/src-3.0/GF/Formalism/FCFG.hs
2008-05-21 13:10:54 +00:00

106 lines
2.7 KiB
Haskell

----------------------------------------------------------------------
-- |
-- Maintainer : Krasimir Angelov
-- Stability : (stable)
-- Portability : (portable)
--
-- Definitions of fast multiple context-free grammars
-----------------------------------------------------------------------------
module GF.Formalism.FCFG
(
-- * Token
FToken
-- * Category
, FPath
, FCat
, fcatString, fcatInt, fcatFloat, fcatVar
-- * Symbol
, FIndex
, FSymbol(..)
-- * Name
, FName
, isCoercionF
-- * Grammar
, FPointPos
, FGrammar
, FRule(..)
) where
import Control.Monad (liftM)
import Data.List (groupBy)
import Data.Array
import qualified Data.Map as Map
import GF.Formalism.Utilities
import qualified GF.GFCC.CId as AbsGFCC
import GF.Infra.PrintClass
------------------------------------------------------------
-- Token
type FToken = String
------------------------------------------------------------
-- Category
type FPath = [FIndex]
type FCat = Int
fcatString, fcatInt, fcatFloat, fcatVar :: Int
fcatString = (-1)
fcatInt = (-2)
fcatFloat = (-3)
fcatVar = (-4)
------------------------------------------------------------
-- Symbol
type FIndex = Int
data FSymbol
= FSymCat {-# UNPACK #-} !FCat {-# UNPACK #-} !FIndex {-# UNPACK #-} !Int
| FSymTok FToken
------------------------------------------------------------
-- Name
type FName = NameProfile AbsGFCC.CId
isCoercionF :: FName -> Bool
isCoercionF (Name fun [Unify [0]]) = fun == AbsGFCC.wildCId
isCoercionF _ = False
------------------------------------------------------------
-- Grammar
type FPointPos = Int
type FGrammar = ([FRule], Map.Map AbsGFCC.CId [FCat])
data FRule = FRule FName [FCat] FCat (Array FIndex (Array FPointPos FSymbol))
------------------------------------------------------------
-- pretty-printing
instance Print AbsGFCC.CId where
prt = AbsGFCC.prCId
instance Print FSymbol where
prt (FSymCat c l n) = "($" ++ prt n ++ "!" ++ prt l ++ ")"
prt (FSymTok t) = simpleShow (prt t)
where simpleShow str = "\"" ++ concatMap mkEsc str ++ "\""
mkEsc '\\' = "\\\\"
mkEsc '\"' = "\\\""
mkEsc '\n' = "\\n"
mkEsc '\t' = "\\t"
mkEsc chr = [chr]
prtList = prtSep " "
instance Print FRule where
prt (FRule name args res lins) = prt name ++ " : " ++ (if null args then "" else prtSep " " args ++ " -> ") ++ prt res ++
" =\n [" ++ prtSep "\n " ["("++prtSep " " [prt sym | (_,sym) <- assocs syms]++")" | (_,syms) <- assocs lins]++"]"
prtList = prtSep "\n"