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gf-core/src/GF/Conversion/SimpleToFCFG.hs
2006-06-01 11:29:30 +00:00

456 lines
20 KiB
Haskell

----------------------------------------------------------------------
-- |
-- Maintainer : Krasimir Angelov
-- Stability : (stable)
-- Portability : (portable)
--
-- Converting SimpleGFC grammars to fast nonerasing MCFG grammar.
--
-- the resulting grammars might be /very large/
--
-- the conversion is only equivalent if the GFC grammar has a context-free backbone.
-----------------------------------------------------------------------------
module GF.Conversion.SimpleToFCFG
(convertGrammar) where
import GF.System.Tracing
import GF.Infra.Print
import GF.Infra.Ident
import Control.Monad
import GF.Formalism.Utilities
import GF.Formalism.GCFG
import GF.Formalism.FCFG
import GF.Formalism.MCFG(Lin(..))
import GF.Formalism.SimpleGFC
import GF.Conversion.Types
import GF.Canon.AbsGFC(CIdent(..))
import GF.Data.BacktrackM
import GF.Data.SortedList
import GF.Data.Utilities (updateNthM)
import qualified Data.Map as Map
import qualified Data.Set as Set
import qualified Data.List as List
import Data.Array
----------------------------------------------------------------------
-- main conversion function
convertGrammar :: SGrammar -> FGrammar
convertGrammar srules = getFRules (loop frulesEnv)
where
(srulesMap,frulesEnv) = foldl helper (Map.empty,emptyFRulesEnv) srules
where
helper (srulesMap,frulesEnv) rule@(Rule (Abs decl _ _) (Cnc ctype _ _)) =
( Map.insertWith (++) (decl2cat decl) [rule] srulesMap
, foldBM (\selector _ env -> convertRule selector rule env)
frulesEnv
(mkSingletonSelector ctype)
()
)
loop frulesEnv =
let (todo, frulesEnv') = takeToDoRules srulesMap frulesEnv
in case todo of
[] -> frulesEnv'
_ -> loop $! foldl (\env (srules,selector) ->
foldl (\env srule -> convertRule selector srule env) env srules) frulesEnv' todo
----------------------------------------------------------------------
-- rule conversion
convertRule :: STermSelector -> SRule -> FRulesEnv -> FRulesEnv
convertRule selector (Rule (Abs decl decls (Name fun profile)) (Cnc ctype ctypes (Just term))) frulesEnv =
foldBM addRule
frulesEnv
(convertTerm selector term [Lin emptyPath []])
(let cat : args = map decl2cat (decl : decls)
in (initialFCat cat, map initialFCat args, ctype, ctypes))
where
addRule linRec (newCat', newArgs', _, _) env0 =
let (env1, newCat) = genFCatHead env0 newCat'
(env2, newArgs,idxArgs) = foldr (\(fcat,ctype,idx) (env,args,all_args) ->
let (env1, fcat1) = genFCatArg env fcat ctype
in case fcat of
FCat _ _ [] _ -> (env , args, all_args)
_ -> (env1,fcat1:args,(idx,fcat1):all_args)) (env1,[],[]) (zip3 newArgs' ctypes [0..])
(catPaths : argsPaths) = [rcs | (FCat _ _ rcs _) <- (newCat : newArgs)]
newLinRec = listArray (0,length linRec-1) [translateLin idxArgs path linRec | path <- catPaths]
(_,newProfile) = List.mapAccumL accumProf 0 newArgs'
where
accumProf nr (FCat _ _ [] _) = (nr, Unify [] )
accumProf nr _ = (nr+1, Unify [nr])
newName = Name fun (profile `composeProfiles` newProfile)
rule = FRule (Abs newCat newArgs (Name fun newProfile)) newLinRec
in addFCatRule env2 rule
convertRule selector _ frulesEnv = frulesEnv
translateLin idxArgs lbl' [] = array (0,-1) []
translateLin idxArgs lbl' (Lin lbl syms : lins)
| lbl' == lbl = listArray (0,length syms-1) (map instSym syms)
| otherwise = translateLin idxArgs lbl' lins
where instSym = symbol (\(_, lbl, nr) -> instCat lbl nr 0 idxArgs) FSymTok
instCat lbl nr nr' ((idx,arg@(FCat _ _ rcs _)):idxArgs)
| nr == idx = FSymCat arg (index lbl rcs 0) nr'
| otherwise = instCat lbl nr (nr'+1) idxArgs
index lbl' (lbl:lbls) idx
| lbl' == lbl = idx
| otherwise = index lbl' lbls $! (idx+1)
----------------------------------------------------------------------
-- term conversion
type CnvMonad a = BacktrackM Env a
type Env = (FCat, [FCat], SLinType, [SLinType])
type LinRec = [Lin SCat SPath Token]
convertTerm :: STermSelector -> STerm -> LinRec -> CnvMonad LinRec
convertTerm selector (Arg nr cat path) (Lin lbl_path lin : lins) = convertArg selector nr cat path lbl_path lin lins
convertTerm selector (con :^ args) (Lin lbl_path lin : lins) = convertCon selector con args lbl_path lin lins
convertTerm selector (Rec record) (Lin lbl_path lin : lins) = convertRec selector record lbl_path lin lins
convertTerm selector (term :. lbl) lins = convertTerm (RecPrj lbl selector) term lins
convertTerm selector (Tbl table) (Lin lbl_path lin : lins) = convertTbl selector table lbl_path lin lins
convertTerm selector (term :! sel) lins = do sel <- evalTerm sel
convertTerm (TblPrj sel selector) term lins
convertTerm selector (Variants vars) lins = do term <- member vars
convertTerm selector term lins
convertTerm selector (t1 :++ t2) lins = do lins <- convertTerm selector t2 lins
lins <- convertTerm selector t1 lins
return lins
convertTerm selector (Token str) (Lin lbl_path lin : lins) = do projectHead lbl_path
return (Lin lbl_path (Tok str : lin) : lins)
convertTerm selector (Empty ) (Lin lbl_path lin : lins) = do projectHead lbl_path
return (Lin lbl_path lin : lins)
convertArg (RecSel record) nr cat path lbl_path lin lins =
foldM (\lins (lbl, selector) -> convertArg selector nr cat (path ++. lbl) (lbl_path ++. lbl) lin lins) lins record
convertArg (TblSel cases) nr cat path lbl_path lin lins =
foldM (\lins (term, selector) -> convertArg selector nr cat (path ++! term) (lbl_path ++! term) lin lins) lins cases
convertArg (RecPrj lbl selector) nr cat path lbl_path lin lins =
convertArg selector nr cat (path ++. lbl ) lbl_path lin lins
convertArg (TblPrj term selector) nr cat path lbl_path lin lins =
convertArg selector nr cat (path ++! term) lbl_path lin lins
convertArg (ConSel terms) nr cat path lbl_path lin lins = do
sel <- member terms
restrictHead lbl_path sel
restrictArg nr lbl_path sel
return lins
convertArg StrSel nr cat path lbl_path lin lins = do
projectHead lbl_path
projectArg nr path
return (Lin lbl_path (Cat (cat, path, nr) : lin) : lins)
convertCon (ConSel terms) con args lbl_path lin lins = do
args <- mapM evalTerm args
let term = con :^ args
guard (term `elem` terms)
restrictHead lbl_path term
return lins
convertRec selector [] lbl_path lin lins = return lins
convertRec selector@(RecSel fields) ((label, val):record) lbl_path lin lins = select fields
where
select [] = convertRec selector record lbl_path lin lins
select ((label',sub_sel) : fields)
| label == label' = do lins <- convertTerm sub_sel val (Lin (lbl_path ++. label) lin : lins)
convertRec selector record lbl_path lin lins
| otherwise = select fields
convertRec (RecPrj label sub_sel) record lbl_path lin lins = do
(label',val) <- member record
guard (label==label')
convertTerm sub_sel val (Lin lbl_path lin : lins)
convertTbl selector [] lbl_path lin lins = return lins
convertTbl selector@(TblSel cases) ((term, val):table) lbl_path lin lins = case selector of { TblSel cases -> select cases }
where
select [] = convertTbl selector table lbl_path lin lins
select ((term',sub_sel) : cases)
| term == term' = do lins <- convertTerm sub_sel val (Lin (lbl_path ++! term) lin : lins)
convertTbl selector table lbl_path lin lins
| otherwise = select cases
convertTbl (TblPrj term sub_sel) table lbl_path lin lins = do
(term',val) <- member table
guard (term==term')
convertTerm sub_sel val (Lin lbl_path lin : lins)
------------------------------------------------------------
-- eval a term to ground terms
evalTerm :: STerm -> CnvMonad STerm
evalTerm arg@(Arg nr _ path) = do ctype <- readArgCType nr
unifyPType arg $ lintypeFollowPath path ctype
evalTerm (con :^ terms) = do terms <- mapM evalTerm terms
return (con :^ terms)
evalTerm (Rec record) = do record <- mapM evalAssign record
return (Rec record)
evalTerm (term :. lbl) = do term <- evalTerm term
evalTerm (term +. lbl)
evalTerm (Tbl table) = do table <- mapM evalCase table
return (Tbl table)
evalTerm (term :! sel) = do sel <- evalTerm sel
evalTerm (term +! sel)
evalTerm (Variants terms) = member terms >>= evalTerm
evalTerm (t1 :++ t2) = do t1 <- evalTerm t1
t2 <- evalTerm t2
return (t1 :++ t2)
evalTerm (Token str) = do return (Token str)
evalTerm Empty = do return Empty
evalAssign :: (Label, STerm) -> CnvMonad (Label, STerm)
evalAssign (lbl, term) = liftM ((,) lbl) $ evalTerm term
evalCase :: (STerm, STerm) -> CnvMonad (STerm, STerm)
evalCase (pat, term) = liftM2 (,) (evalTerm pat) (evalTerm term)
unifyPType :: STerm -> SLinType -> CnvMonad STerm
unifyPType arg (RecT prec) =
liftM Rec $
sequence [ liftM ((,) lbl) $
unifyPType (arg +. lbl) ptype |
(lbl, ptype) <- prec ]
unifyPType (Arg nr _ path) (ConT terms) =
do (_, args, _, _) <- readState
let (FCat _ _ _ tcs) = args !! nr
case lookup path tcs of
Just term -> return term
Nothing -> do term <- member terms
restrictArg nr path term
return term
----------------------------------------------------------------------
-- FRulesEnv
data FRulesEnv = FRulesEnv {-# UNPACK #-} !Int FCatSet [FRule]
type SRulesMap = Map.Map SCat [SRule]
type FCatSet = Map.Map SCat (Map.Map [SPath] (Map.Map [(SPath,STerm)] (Either FCat FCat)))
emptyFRulesEnv = FRulesEnv 0 Map.empty []
genFCatHead :: FRulesEnv -> FCat -> (FRulesEnv, FCat)
genFCatHead env@(FRulesEnv last_id fcatSet rules) m1@(FCat _ cat rcs tcs) =
case Map.lookup cat fcatSet >>= Map.lookup rcs >>= Map.lookup tcs of
Just (Left fcat) -> (FRulesEnv last_id (ins fcat) rules, fcat)
Just (Right fcat) -> (env, fcat)
Nothing -> let next_id = last_id+1
fcat = FCat next_id cat rcs tcs
in (FRulesEnv next_id (ins fcat) rules, fcat)
where
ins fcat = Map.insertWith (\_ -> Map.insertWith (\_ -> Map.insert tcs x_fcat) rcs tmap_s) cat rmap_s fcatSet
where
x_fcat = Right fcat
tmap_s = Map.singleton tcs x_fcat
rmap_s = Map.singleton rcs tmap_s
genFCatArg :: FRulesEnv -> FCat -> SLinType -> (FRulesEnv, FCat)
genFCatArg env@(FRulesEnv last_id fcatSet rules) m1@(FCat _ cat rcs tcs) ctype =
case Map.lookup cat fcatSet >>= Map.lookup rcs of
Just tmap -> case Map.lookup tcs tmap of
Just (Left fcat) -> (env, fcat)
Just (Right fcat) -> (env, fcat)
Nothing -> ins tmap
Nothing -> ins Map.empty
where
ins tmap =
let next_id = last_id+1
fcat = FCat next_id cat rcs tcs
(x_fcat,last_id1,tmap1,rules1)
= foldBM (\tcs st (x_fcat,last_id,tmap,rules) ->
let (last_id1,tmap1,fcat_arg) = addArg tcs last_id tmap
rule = FRule (Abs fcat [fcat_arg] coercionName)
(listArray (0,length rcs-1) [listArray (0,0) [FSymCat fcat_arg lbl 0] | lbl <- [0..length rcs-1]])
in if st
then (Right fcat,last_id1,tmap1,rule:rules)
else (x_fcat, last_id, tmap, rules))
(Left fcat,next_id,Map.insert tcs x_fcat tmap,rules)
(gen_tcs ctype emptyPath [])
False
rmap1 = Map.singleton rcs tmap1
in (FRulesEnv last_id1 (Map.insertWith (\_ -> Map.insert rcs tmap1) cat rmap1 fcatSet) rules1, fcat)
where
addArg tcs last_id tmap =
case Map.lookup tcs tmap of
Just (Left fcat) -> (last_id, tmap, fcat)
Just (Right fcat) -> (last_id, tmap, fcat)
Nothing -> let next_id = last_id+1
fcat = FCat next_id cat rcs tcs
in (next_id, Map.insert tcs (Left fcat) tmap, fcat)
gen_tcs :: SLinType -> SPath -> [(SPath,STerm)] -> BacktrackM Bool [(SPath,STerm)]
gen_tcs (RecT record) path acc = foldM (\acc (label,ctype) -> gen_tcs ctype (path ++. label) acc) acc record
gen_tcs (TblT terms ctype) path acc = foldM (\acc term -> gen_tcs ctype (path ++! term ) acc) acc terms
gen_tcs (StrT) path acc = return acc
gen_tcs (ConT terms) path acc =
case List.lookup path tcs of
Just term -> return ((path,term) : acc)
Nothing -> do writeState True
term <- member terms
return ((path,term) : acc)
takeToDoRules :: SRulesMap -> FRulesEnv -> ([([SRule], STermSelector)], FRulesEnv)
takeToDoRules srulesMap (FRulesEnv last_id fcatSet rules) = (todo,FRulesEnv last_id fcatSet' rules)
where
(todo,fcatSet') =
Map.mapAccumWithKey (\todo cat rmap ->
let (todo1,rmap1) = Map.mapAccumWithKey (\todo rcs tmap ->
let (tcss,tmap') = Map.mapAccumWithKey (\tcss tcs x_fcat ->
case x_fcat of
Left fcat -> (tcs:tcss,Right fcat)
Right fcat -> ( tcss, x_fcat)) [] tmap
in case tcss of
[] -> ( todo,tmap )
_ -> ((srules,mkSelector rcs tcss) : todo,tmap')) todo rmap
mb_srules = Map.lookup cat srulesMap
Just srules = mb_srules
in case mb_srules of
Just srules -> (todo1,rmap1)
Nothing -> (todo ,rmap1)) [] fcatSet
addFCatRule :: FRulesEnv -> FRule -> FRulesEnv
addFCatRule (FRulesEnv last_id fcatSet rules) rule = FRulesEnv last_id fcatSet (rule:rules)
getFRules :: FRulesEnv -> [FRule]
getFRules (FRulesEnv last_id fcatSet rules) = rules
------------------------------------------------------------
-- The STermSelector
data STermSelector
= RecSel [(Label, STermSelector)]
| TblSel [(STerm, STermSelector)]
| RecPrj Label STermSelector
| TblPrj STerm STermSelector
| ConSel [STerm]
| StrSel
deriving Show
mkSingletonSelector :: SLinType -> BacktrackM () STermSelector
mkSingletonSelector ctype = do
let (rcss,tcss) = loop emptyPath ([],[]) ctype
rcs <- member rcss
return (mkSelector [rcs] tcss)
where
loop path st (RecT record) = foldl (\st (lbl,ctype) -> loop (path ++. lbl ) st ctype) st record
loop path st (TblT terms ctype) = foldl (\st term -> loop (path ++! term) st ctype) st terms
loop path (rcss,tcss) (ConT terms) = (rcss, map ((,) path) terms : tcss)
loop path (rcss,tcss) (StrT) = (path : rcss, tcss)
mkSelector :: [SPath] -> [[(SPath,STerm)]] -> STermSelector
mkSelector rcs tcss =
foldl addRestriction (case xs of
(path:xs) -> foldl addProjection (path2selector StrSel path) xs) ys
where
xs = [ reverse path | Path path <- rcs]
ys = [(reverse path,term) | tcs <- tcss, (Path path,term) <- tcs]
addProjection :: STermSelector -> [Either Label STerm] -> STermSelector
addProjection StrSel [] = StrSel
addProjection (RecSel fields) (Left lbl : path) = RecSel (add fields)
where
add [] = [(lbl,path2selector StrSel path)]
add (field@(lbl',sub_sel):fields)
| lbl == lbl' = (lbl',addProjection sub_sel path):fields
| otherwise = field : add fields
addProjection (TblSel cases) (Right pat : path) = TblSel (add cases)
where
add [] = [(pat,path2selector StrSel path)]
add (cas@(pat',sub_sel):cases)
| pat == pat' = (pat',addProjection sub_sel path):cases
| otherwise = cas : add cases
addProjection x y = error ("addProjection "++show x ++ " " ++ prt (Path y))
addRestriction :: STermSelector -> ([Either Label STerm],STerm) -> STermSelector
addRestriction (ConSel terms) ([] ,term) = ConSel (term:terms)
addRestriction (RecSel fields) (Left lbl : path,term) = RecSel (add fields)
where
add [] = [(lbl,path2selector (ConSel [term]) path)]
add (field@(lbl',sub_sel):fields)
| lbl == lbl' = (lbl',addRestriction sub_sel (path,term)):fields
| otherwise = field : add fields
addRestriction (TblSel cases) (Right pat : path,term) = TblSel (add cases)
where
add [] = [(pat,path2selector (ConSel [term]) path)]
add (field@(pat',sub_sel):cases)
| pat == pat' = (pat',addRestriction sub_sel (path,term)):cases
| otherwise = field : add cases
path2selector base [] = base
path2selector base (Left lbl : path) = RecSel [(lbl,path2selector base path)]
path2selector base (Right sel : path) = TblSel [(sel,path2selector base path)]
------------------------------------------------------------
-- updating the MCF rule
readArgCType :: Int -> CnvMonad SLinType
readArgCType arg = do (_, _, _, ctypes) <- readState
return (ctypes !! arg)
restrictArg :: Int -> SPath -> STerm -> CnvMonad ()
restrictArg arg path term
= do (head, args, ctype, ctypes) <- readState
args' <- updateNthM (restrictFCat path term) arg args
writeState (head, args', ctype, ctypes)
projectArg :: Int -> SPath -> CnvMonad ()
projectArg arg path
= do (head, args, ctype, ctypes) <- readState
args' <- updateNthM (projectFCat path) arg args
writeState (head, args', ctype, ctypes)
readHeadCType :: CnvMonad SLinType
readHeadCType = do (_, _, ctype, _) <- readState
return ctype
restrictHead :: SPath -> STerm -> CnvMonad ()
restrictHead path term
= do (head, args, ctype, ctypes) <- readState
head' <- restrictFCat path term head
writeState (head', args, ctype, ctypes)
projectHead :: SPath -> CnvMonad ()
projectHead path
= do (head, args, ctype, ctypes) <- readState
head' <- projectFCat path head
writeState (head', args, ctype, ctypes)
restrictFCat :: SPath -> STerm -> FCat -> CnvMonad FCat
restrictFCat path0 term0 (FCat id cat rcs tcs) = do
tcs <- addConstraint tcs
return (FCat id cat rcs tcs)
where
addConstraint (c@(path,term) : cs)
| path0 > path = liftM (c:) (addConstraint cs)
| path0 == path = guard (term0 == term) >>
return (c : cs)
addConstraint cs = return ((path0,term0) : cs)
projectFCat :: SPath -> FCat -> CnvMonad FCat
projectFCat path0 (FCat id cat rcs tcs) = do
return (FCat id cat (addConstraint rcs) tcs)
where
addConstraint (path : rcs)
| path0 > path = path : addConstraint rcs
| path0 == path = path : rcs
addConstraint rcs = path0 : rcs