mirror of
https://github.com/GrammaticalFramework/gf-core.git
synced 2026-04-11 05:49:31 -06:00
456 lines
20 KiB
Haskell
456 lines
20 KiB
Haskell
{-# LANGUAGE BangPatterns, RankNTypes, FlexibleInstances, MultiParamTypeClasses #-}
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----------------------------------------------------------------------
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-- |
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-- Maintainer : Krasimir Angelov
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-- Stability : (stable)
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-- Portability : (portable)
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--
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-- Convert PGF grammar to PMCFG grammar.
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--
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-----------------------------------------------------------------------------
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module GF.Compile.GeneratePMCFG
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(convertConcrete) where
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import PGF.CId
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import PGF.Data
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import PGF.Macros
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import GF.Data.BacktrackM
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import GF.Data.Utilities (updateNthM, updateNth, sortNub)
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import qualified Data.Map as Map
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import qualified Data.Set as Set
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import qualified Data.List as List
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import qualified Data.IntMap as IntMap
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import qualified Data.ByteString.Char8 as BS
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import Data.Array.IArray
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import Data.Maybe
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import Control.Monad
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import Debug.Trace
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----------------------------------------------------------------------
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-- main conversion function
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convertConcrete :: Abstr -> Concr -> ParserInfo
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convertConcrete abs cnc = convert abs_defs conc cats
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where abs_defs = Map.assocs (funs abs)
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conc = Map.union (opers cnc) (lins cnc) -- "union big+small most efficient"
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cats = lincats cnc
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convert :: [(CId,(Type,Int,[Equation]))] -> TermMap -> TermMap -> ParserInfo
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convert abs_defs cnc_defs cat_defs =
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let env = expandHOAS abs_defs cnc_defs cat_defs (emptyGrammarEnv cnc_defs cat_defs)
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in getParserInfo (List.foldl' (convertRule cnc_defs) env pfrules)
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where
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pfrules = [
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(PFRule id args (0,res) (map findLinType args) (findLinType (0,res)) term) |
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(id, (ty,_,_)) <- abs_defs, let (args,res) = typeSkeleton ty,
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term <- maybeToList (Map.lookup id cnc_defs)]
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findLinType (_,id) = fromMaybe (error $ "No lincat for " ++ show id) (Map.lookup id cat_defs)
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brk :: (GrammarEnv -> GrammarEnv) -> (GrammarEnv -> GrammarEnv)
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brk f (GrammarEnv last_id catSet seqSet funSet crcSet prodSet) =
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case f (GrammarEnv last_id catSet seqSet funSet crcSet IntMap.empty) of
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(GrammarEnv last_id catSet seqSet funSet crcSet topdown1) -> IntMap.foldWithKey optimize (GrammarEnv last_id catSet seqSet funSet crcSet prodSet) topdown1
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where
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optimize cat ps env = IntMap.foldWithKey ff env (IntMap.fromListWith (++) [(funid,[args]) | FApply funid args <- Set.toList ps])
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where
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ff :: FunId -> [[FCat]] -> GrammarEnv -> GrammarEnv
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ff funid xs env
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| product (map Set.size ys) == count =
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case List.mapAccumL (\env c -> addFCoercion env (Set.toList c)) env ys of
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(env,args) -> addProduction env cat (FApply funid args)
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| otherwise = List.foldl (\env args -> addProduction env cat (FApply funid args)) env xs
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where
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count = length xs
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ys = foldr (zipWith Set.insert) (repeat Set.empty) xs
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convertRule :: TermMap -> GrammarEnv -> ProtoFRule -> GrammarEnv
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convertRule cnc_defs grammarEnv (PFRule fun args res ctypes ctype term) =
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let pres = protoFCat cnc_defs res ctype
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pargs = zipWith (protoFCat cnc_defs) args ctypes
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b = runBranchM (convertTerm cnc_defs [] ctype term) (pargs,[])
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(grammarEnv1,b1) = addSequences' grammarEnv b
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grammarEnv2 = brk (\grammarEnv -> foldBM addRule
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grammarEnv
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(go' b1 [] [])
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(pres,pargs) ) grammarEnv1
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in grammarEnv2
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where
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addRule lins (newCat', newArgs') env0 =
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let [newCat] = getFCats env0 newCat'
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(env1, newArgs) = List.mapAccumL (\env -> addFCoercion env . getFCats env) env0 newArgs'
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(env2,funid) = addFFun env1 (FFun fun [[n] | n <- [0..length newArgs-1]] (mkArray lins))
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in addProduction env2 newCat (FApply funid newArgs)
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----------------------------------------------------------------------
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-- Branch monad
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newtype BranchM a = BM (forall b . (a -> ([ProtoFCat],[FSymbol]) -> Branch b) -> ([ProtoFCat],[FSymbol]) -> Branch b)
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instance Monad BranchM where
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return a = BM (\c s -> c a s)
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BM m >>= k = BM (\c s -> m (\a s -> unBM (k a) c s) s)
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where unBM (BM m) = m
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instance MonadState ([ProtoFCat],[FSymbol]) BranchM where
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get = BM (\c s -> c s s)
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put s = BM (\c _ -> c () s)
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instance Functor BranchM where
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fmap f (BM m) = BM (\c s -> m (c . f) s)
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runBranchM :: BranchM (Value a) -> ([ProtoFCat],[FSymbol]) -> Branch a
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runBranchM (BM m) s = m (\v s -> Return v) s
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variants :: [a] -> BranchM a
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variants xs = BM (\c s -> Variant (go xs c s))
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where
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go [] c s = []
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go (x:xs) c s = c x s : go xs c s
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choices :: Int -> FPath -> BranchM FIndex
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choices nr path = BM (\c s -> let (args,_) = s
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PFCat _ _ _ tcs = args !! nr
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in case fromMaybe (error "evalTerm: wrong path") (lookup path tcs) of
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[index] -> c index s
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indices -> Case nr path (go indices c s))
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where
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go [] c s = []
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go (i:is) c s = (c i (updateEnv i s)) : go is c s
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updateEnv index (args,seq) = (updateNth (restrictArg path index) nr args,seq)
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restrictArg path index (PFCat n cat rcs tcs) = PFCat n cat rcs (addConstraint path index tcs)
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addConstraint path0 index0 [] = error "restrictProtoFCat: unknown path"
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addConstraint path0 index0 (c@(path,indices) : tcs)
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| path0 == path = ((path,[index0]) : tcs)
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| otherwise = c : addConstraint path0 index0 tcs
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mkRecord :: [BranchM (Value a)] -> BranchM (Value a)
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mkRecord xs = BM (\c -> go xs (c . Rec))
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where
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go [] c s = c [] s
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go (BM m:fs) c s = go fs (\bs s -> c (m (\v s -> Return v) s : bs) s) s
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-- cutBranch :: BranchM (Value a) -> BranchM (Branch a)
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-- cutBranch (BM m) = BM (\c e -> c (m (\v e -> Return v) e) e)
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----------------------------------------------------------------------
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-- term conversion
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type CnvMonad a = BranchM a
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type FPath = [FIndex]
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data ProtoFCat = PFCat Int CId [FPath] [(FPath,[FIndex])]
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type Env = (ProtoFCat, [ProtoFCat])
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data ProtoFRule = PFRule CId {- function -}
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[(Int,CId)] {- argument types: context size and category -}
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(Int,CId) {- result type : context size (always 0) and category -}
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[Term] {- argument lin-types representation -}
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Term {- result lin-type representation -}
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Term {- body -}
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type TermMap = Map.Map CId Term
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protoFCat :: TermMap -> (Int,CId) -> Term -> ProtoFCat
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protoFCat cnc_defs (n,cat) ctype =
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let (rcs,tcs) = loop [] [] [] ctype'
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in PFCat n cat rcs tcs
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where
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ctype' -- extend the high-order linearization type
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| n > 0 = case ctype of
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R xs -> R (xs ++ replicate n (S []))
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_ -> error $ "Not a record: " ++ show ctype
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| otherwise = ctype
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loop path rcs tcs (R record) = List.foldl' (\(rcs,tcs) (index,term) -> loop (index:path) rcs tcs term) (rcs,tcs) (zip [0..] record)
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loop path rcs tcs (C i) = ( rcs,(path,[0..i]):tcs)
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loop path rcs tcs (S _) = (path:rcs, tcs)
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loop path rcs tcs (F id) = case Map.lookup id cnc_defs of
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Just term -> loop path rcs tcs term
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Nothing -> error ("unknown identifier: "++show id)
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data Branch a
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= Case Int FPath [Branch a]
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| Variant [Branch a]
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| Return (Value a)
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data Value a
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= Rec [Branch a]
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| Str a
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| Con FIndex
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go' :: Branch SeqId -> FPath -> [SeqId] -> BacktrackM Env [SeqId]
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go' (Case nr path_ bs) path ss = do (index,b) <- member (zip [0..] bs)
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restrictArg nr path_ index
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go' b path ss
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go' (Variant bs) path ss = do b <- member bs
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go' b path ss
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go' (Return v) path ss = go v path ss
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go :: Value SeqId -> FPath -> [SeqId] -> BacktrackM Env [SeqId]
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go (Rec xs) path ss = foldM (\ss (lbl,b) -> go' b (lbl:path) ss) ss (zip [0..] xs)
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go (Str seqid) path ss = return (seqid : ss)
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go (Con i) path ss = restrictHead path i >> return ss
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addSequences' :: GrammarEnv -> Branch [FSymbol] -> (GrammarEnv, Branch SeqId)
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addSequences' env (Case nr path bs) = let (env1,bs1) = List.mapAccumL addSequences' env bs
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in (env1,Case nr path bs1)
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addSequences' env (Variant bs) = let (env1,bs1) = List.mapAccumL addSequences' env bs
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in (env1,Variant bs1)
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addSequences' env (Return v) = let (env1,v1) = addSequences env v
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in (env1,Return v1)
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addSequences :: GrammarEnv -> Value [FSymbol] -> (GrammarEnv, Value SeqId)
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addSequences env (Rec vs) = let (env1,vs1) = List.mapAccumL addSequences' env vs
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in (env1,Rec vs1)
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addSequences env (Str lin) = let (env1,seqid) = addFSeq env lin
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in (env1,Str seqid)
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addSequences env (Con i) = (env,Con i)
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convertTerm :: TermMap -> FPath -> Term -> Term -> CnvMonad (Value [FSymbol])
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convertTerm cnc_defs sel ctype (V nr) = convertArg ctype nr (reverse sel)
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convertTerm cnc_defs sel ctype (C nr) = convertCon ctype nr (reverse sel)
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convertTerm cnc_defs sel ctype (R record) = convertRec cnc_defs sel ctype record
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convertTerm cnc_defs sel ctype (P term p) = do nr <- evalTerm cnc_defs [] p
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convertTerm cnc_defs (nr:sel) ctype term
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convertTerm cnc_defs sel ctype (FV vars) = do term <- variants vars
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convertTerm cnc_defs sel ctype term
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convertTerm cnc_defs sel ctype (S ts) = do vs <- mapM (convertTerm cnc_defs sel ctype) ts
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return (Str (concat [s | Str s <- vs]))
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--convertTerm cnc_defs sel ctype (K t) = return (Str [FSymTok t])
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convertTerm cnc_defs sel ctype (K (KS t)) = return (Str [FSymTok (KS t)])
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convertTerm cnc_defs sel ctype (K (KP strs vars)) =
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do toks <- variants (strs:[strs' | Alt strs' _ <- vars])
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return (Str (map (FSymTok . KS) toks))
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convertTerm cnc_defs sel ctype (F id) = case Map.lookup id cnc_defs of
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Just term -> convertTerm cnc_defs sel ctype term
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Nothing -> error ("unknown id " ++ prCId id)
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convertTerm cnc_defs sel ctype (W s t) = do
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ss <- case t of
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R ss -> return ss
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F f -> case Map.lookup f cnc_defs of
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Just (R ss) -> return ss
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_ -> error ("unknown id " ++ prCId f)
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convertRec cnc_defs sel ctype [K (KS (s ++ s1)) | K (KS s1) <- ss]
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convertTerm cnc_defs sel ctype x = error ("convertTerm ("++show x++")")
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convertArg :: Term -> Int -> FPath -> CnvMonad (Value [FSymbol])
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convertArg (R ctypes) nr path = do
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mkRecord (zipWith (\lbl ctype -> convertArg ctype nr (lbl:path)) [0..] ctypes)
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convertArg (C max) nr path = do
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index <- choices nr path
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return (Con index)
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convertArg (S _) nr path = do
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(args,_) <- get
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let PFCat _ cat rcs tcs = args !! nr
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l = index path rcs 0
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sym | isLiteralCat cat = FSymLit nr l
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| otherwise = FSymCat nr l
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return (Str [sym])
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where
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index lbl' (lbl:lbls) idx
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| lbl' == lbl = idx
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| otherwise = index lbl' lbls $! (idx+1)
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convertCon (C max) index [] = return (Con index)
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convertCon x _ _ = fail $ "SimpleToFCFG.convertCon: " ++ show x
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convertRec cnc_defs [] (R ctypes) record = do
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mkRecord (zipWith (convertTerm cnc_defs []) ctypes record)
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convertRec cnc_defs (index:sub_sel) ctype record =
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convertTerm cnc_defs sub_sel ctype (record !! index)
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------------------------------------------------------------
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-- eval a term to ground terms
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evalTerm :: TermMap -> FPath -> Term -> CnvMonad FIndex
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evalTerm cnc_defs path (V nr) = choices nr (reverse path)
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evalTerm cnc_defs path (C nr) = return nr
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evalTerm cnc_defs path (R record) = case path of
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(index:path) -> evalTerm cnc_defs path (record !! index)
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evalTerm cnc_defs path (P term sel) = do index <- evalTerm cnc_defs [] sel
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evalTerm cnc_defs (index:path) term
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evalTerm cnc_defs path (FV terms) = variants terms >>= evalTerm cnc_defs path
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evalTerm cnc_defs path (F id) = case Map.lookup id cnc_defs of
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Just term -> evalTerm cnc_defs path term
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Nothing -> error ("unknown id " ++ prCId id)
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evalTerm cnc_defs path x = error ("evalTerm ("++show x++")")
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----------------------------------------------------------------------
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-- GrammarEnv
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data GrammarEnv = GrammarEnv {-# UNPACK #-} !Int CatSet SeqSet FunSet CoerceSet (IntMap.IntMap (Set.Set Production))
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type CatSet = IntMap.IntMap (Map.Map CId (FCat,FCat,[Int]))
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type SeqSet = Map.Map FSeq SeqId
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type FunSet = Map.Map FFun FunId
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type CoerceSet= Map.Map [FCat] FCat
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emptyGrammarEnv cnc_defs lincats =
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let (last_id,catSet) = Map.mapAccumWithKey computeCatRange 0 lincats
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in GrammarEnv last_id (IntMap.singleton 0 catSet) Map.empty Map.empty Map.empty IntMap.empty
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where
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computeCatRange index cat ctype
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| cat == cidString = (index, (fcatString,fcatString,[]))
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| cat == cidInt = (index, (fcatInt, fcatInt, []))
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| cat == cidFloat = (index, (fcatFloat, fcatFloat, []))
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| otherwise = (index+size,(index,index+size-1,poly))
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where
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(size,poly) = getMultipliers 1 [] ctype
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getMultipliers m ms (R record) = foldl (\(m,ms) t -> getMultipliers m ms t) (m,ms) record
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getMultipliers m ms (S _) = (m,ms)
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getMultipliers m ms (C max_index) = (m*(max_index+1),m : ms)
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getMultipliers m ms (F id) = case Map.lookup id cnc_defs of
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Just term -> getMultipliers m ms term
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Nothing -> error ("unknown identifier: "++prCId id)
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expandHOAS abs_defs cnc_defs lincats env =
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foldl add_varFun (foldl (\env ncat -> add_hoFun (add_hoCat env ncat) ncat) env hoTypes) hoCats
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where
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hoTypes :: [(Int,CId)]
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hoTypes = sortNub [(n,c) | (_,(ty,_,_)) <- abs_defs
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, (n,c) <- fst (typeSkeleton ty), n > 0]
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hoCats :: [CId]
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hoCats = sortNub [c | (_,(ty,_,_)) <- abs_defs
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, Hyp _ ty <- case ty of {DTyp hyps val _ -> hyps}
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, c <- fst (catSkeleton ty)]
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-- add a range of PMCFG categories for each GF high-order category
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add_hoCat env@(GrammarEnv last_id catSet seqSet funSet crcSet prodSet) (n,cat) =
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case IntMap.lookup 0 catSet >>= Map.lookup cat of
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Just (start,end,ms) -> let !catSet' = IntMap.insertWith Map.union n (Map.singleton cat (last_id,last_id+(end-start),ms)) catSet
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!last_id' = last_id+(end-start)+1
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in (GrammarEnv last_id' catSet' seqSet funSet crcSet prodSet)
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Nothing -> env
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-- add one PMCFG function for each high-order type: _B : Cat -> Var -> ... -> Var -> HoCat
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add_hoFun env (n,cat) =
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let linRec = reverse $
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[[FSymCat 0 i] | (l,i) <- case arg of {PFCat _ _ rcs _ -> zip rcs [0..]}] ++
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[[FSymLit i 0] | i <- [1..n]]
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(env1,lins) = List.mapAccumL addFSeq env linRec
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newLinRec = mkArray lins
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(env2,funid) = addFFun env1 (FFun _B [[i] | i <- [0..n]] newLinRec)
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env3 = foldl (\env (arg,res) -> addProduction env res (FApply funid (arg : replicate n fcatVar)))
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env2
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(zip (getFCats env2 arg) (getFCats env2 res))
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in env3
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where
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(arg,res) = case Map.lookup cat lincats of
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Nothing -> error $ "No lincat for " ++ prCId cat
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Just ctype -> (protoFCat cnc_defs (0,cat) ctype, protoFCat cnc_defs (n,cat) ctype)
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-- add one PMCFG function for each high-order category: _V : Var -> Cat
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add_varFun env cat =
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let (env1,seqid) = addFSeq env [FSymLit 0 0]
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lins = replicate (case res of {PFCat _ _ rcs _ -> length rcs}) seqid
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(env2,funid) = addFFun env1 (FFun _V [[0]] (mkArray lins))
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env3 = foldl (\env res -> addProduction env2 res (FApply funid [fcatVar]))
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env2
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(getFCats env2 res)
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in env3
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where
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res = case Map.lookup cat lincats of
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Nothing -> error $ "No lincat for " ++ prCId cat
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Just ctype -> protoFCat cnc_defs (0,cat) ctype
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_B = mkCId "_B"
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_V = mkCId "_V"
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addProduction :: GrammarEnv -> FCat -> Production -> GrammarEnv
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addProduction (GrammarEnv last_id catSet seqSet funSet crcSet prodSet) cat p =
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GrammarEnv last_id catSet seqSet funSet crcSet (IntMap.insertWith Set.union cat (Set.singleton p) prodSet)
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addFSeq :: GrammarEnv -> [FSymbol] -> (GrammarEnv,SeqId)
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addFSeq env@(GrammarEnv last_id catSet seqSet funSet crcSet prodSet) lst =
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case Map.lookup seq seqSet of
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Just id -> (env,id)
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Nothing -> let !last_seq = Map.size seqSet
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in (GrammarEnv last_id catSet (Map.insert seq last_seq seqSet) funSet crcSet prodSet,last_seq)
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where
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seq = mkArray lst
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addFFun :: GrammarEnv -> FFun -> (GrammarEnv,FunId)
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addFFun env@(GrammarEnv last_id catSet seqSet funSet crcSet prodSet) fun =
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case Map.lookup fun funSet of
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Just id -> (env,id)
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Nothing -> let !last_funid = Map.size funSet
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in (GrammarEnv last_id catSet seqSet (Map.insert fun last_funid funSet) crcSet prodSet,last_funid)
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addFCoercion :: GrammarEnv -> [FCat] -> (GrammarEnv,FCat)
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addFCoercion env@(GrammarEnv last_id catSet seqSet funSet crcSet prodSet) sub_fcats =
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case sub_fcats of
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[fcat] -> (env,fcat)
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_ -> case Map.lookup sub_fcats crcSet of
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Just fcat -> (env,fcat)
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Nothing -> let !fcat = last_id+1
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in (GrammarEnv fcat catSet seqSet funSet (Map.insert sub_fcats fcat crcSet) prodSet,fcat)
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getParserInfo :: GrammarEnv -> ParserInfo
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getParserInfo (GrammarEnv last_id catSet seqSet funSet crcSet prodSet) =
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ParserInfo { functions = mkArray funSet
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, sequences = mkArray seqSet
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, productions0= productions0
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, productions = filterProductions productions0
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, startCats = maybe Map.empty (Map.map (\(start,end,_) -> range (start,end))) (IntMap.lookup 0 catSet)
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, totalCats = last_id+1
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}
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where
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mkArray map = array (0,Map.size map-1) [(v,k) | (k,v) <- Map.toList map]
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productions0 = IntMap.union prodSet coercions
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coercions = IntMap.fromList [(fcat,Set.fromList (map FCoerce sub_fcats)) | (sub_fcats,fcat) <- Map.toList crcSet]
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getFCats :: GrammarEnv -> ProtoFCat -> [FCat]
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getFCats (GrammarEnv last_id catSet seqSet funSet crcSet prodSet) (PFCat n cat rcs tcs) =
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case IntMap.lookup n catSet >>= Map.lookup cat of
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Just (start,end,ms) -> reverse (solutions (variants ms tcs start) ())
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where
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variants _ [] fcat = return fcat
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variants (m:ms) ((_,indices) : tcs) fcat = do index <- member indices
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variants ms tcs ((m*index) + fcat)
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------------------------------------------------------------
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-- updating the MCF rule
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restrictArg :: FIndex -> FPath -> FIndex -> BacktrackM Env ()
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restrictArg nr path index = do
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(head, args) <- get
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args' <- updateNthM (restrictProtoFCat path index) nr args
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put (head, args')
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restrictHead :: FPath -> FIndex -> BacktrackM Env ()
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restrictHead path term
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= do (head, args) <- get
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head' <- restrictProtoFCat path term head
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put (head', args)
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restrictProtoFCat :: FPath -> FIndex -> ProtoFCat -> BacktrackM Env ProtoFCat
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restrictProtoFCat path0 index0 (PFCat n cat rcs tcs) = do
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tcs <- addConstraint tcs
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return (PFCat n cat rcs tcs)
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where
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addConstraint [] = error "restrictProtoFCat: unknown path"
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addConstraint (c@(path,indices) : tcs)
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| path0 == path = guard (index0 `elem` indices) >>
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return ((path,[index0]) : tcs)
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| otherwise = liftM (c:) (addConstraint tcs)
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mkArray lst = listArray (0,length lst-1) lst
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