diff options
| author | krasimir <krasimir@chalmers.se> | 2009-12-14 10:54:22 +0000 |
|---|---|---|
| committer | krasimir <krasimir@chalmers.se> | 2009-12-14 10:54:22 +0000 |
| commit | c036459214852ca01868f5da81408f49b22a49e9 (patch) | |
| tree | 72a767680911cba272a033b07fc750c0d4f1d0d3 /src/runtime/haskell/PGF/Parse.hs | |
| parent | faa638d6fc5dbc47d5e3ef3d4da42449005c3a0d (diff) | |
remove the old parsing code and the -erasing=on flag
Diffstat (limited to 'src/runtime/haskell/PGF/Parse.hs')
| -rw-r--r-- | src/runtime/haskell/PGF/Parse.hs | 371 |
1 files changed, 371 insertions, 0 deletions
diff --git a/src/runtime/haskell/PGF/Parse.hs b/src/runtime/haskell/PGF/Parse.hs new file mode 100644 index 000000000..44ff525b4 --- /dev/null +++ b/src/runtime/haskell/PGF/Parse.hs @@ -0,0 +1,371 @@ +{-# LANGUAGE BangPatterns #-}
+module PGF.Parse
+ ( ParseState
+ , ErrorState
+ , initState
+ , nextState
+ , getCompletions
+ , recoveryStates
+ , extractTrees
+ , parse
+ , parseWithRecovery
+ ) where
+
+import Data.Array.IArray
+import Data.Array.Base (unsafeAt)
+import Data.List (isPrefixOf, foldl')
+import Data.Maybe (fromMaybe, maybe)
+import qualified Data.Map as Map
+import qualified GF.Data.TrieMap as TMap
+import qualified Data.IntMap as IntMap
+import qualified Data.Set as Set
+import Control.Monad
+
+import GF.Data.SortedList
+import PGF.CId
+import PGF.Data
+import PGF.Expr(Tree)
+import PGF.Macros
+import PGF.TypeCheck
+import Debug.Trace
+
+parse :: PGF -> Language -> Type -> [String] -> [Tree]
+parse pgf lang typ toks = loop (initState pgf lang typ) toks
+ where
+ loop ps [] = extractTrees ps typ
+ loop ps (t:ts) = case nextState ps t of
+ Left es -> []
+ Right ps -> loop ps ts
+
+parseWithRecovery :: PGF -> Language -> Type -> [Type] -> [String] -> [Tree]
+parseWithRecovery pgf lang typ open_typs toks = accept (initState pgf lang typ) toks
+ where
+ accept ps [] = extractTrees ps typ
+ accept ps (t:ts) =
+ case nextState ps t of
+ Right ps -> accept ps ts
+ Left es -> skip (recoveryStates open_typs es) ts
+
+ skip ps_map [] = extractTrees (fst ps_map) typ
+ skip ps_map (t:ts) =
+ case Map.lookup t (snd ps_map) of
+ Just ps -> accept ps ts
+ Nothing -> skip ps_map ts
+
+-- | Creates an initial parsing state for a given language and
+-- startup category.
+initState :: PGF -> Language -> Type -> ParseState
+initState pgf lang (DTyp _ start _) =
+ let items = do
+ cat <- maybe [] range (Map.lookup start (startCats pinfo))
+ (funid,args) <- foldForest (\funid args -> (:) (funid,args)) (\_ _ args -> args)
+ [] cat (productions pinfo)
+ let FFun fn lins = functions pinfo ! funid
+ (lbl,seqid) <- assocs lins
+ return (Active 0 0 funid seqid args (AK cat lbl))
+
+ pinfo =
+ case lookParser pgf lang of
+ Just pinfo -> pinfo
+ _ -> error ("Unknown language: " ++ showCId lang)
+
+ in PState pgf
+ pinfo
+ (Chart emptyAC [] emptyPC (productions pinfo) (totalCats pinfo) 0)
+ (TMap.singleton [] (Set.fromList items))
+
+-- | From the current state and the next token
+-- 'nextState' computes a new state, where the token
+-- is consumed and the current position is shifted by one.
+-- If the new token cannot be accepted then an error state
+-- is returned.
+nextState :: ParseState -> String -> Either ErrorState ParseState
+nextState (PState pgf pinfo chart items) t =
+ let (mb_agenda,map_items) = TMap.decompose items
+ agenda = maybe [] Set.toList mb_agenda
+ acc = fromMaybe TMap.empty (Map.lookup t map_items)
+ (acc1,chart1) = process (Just t) add (sequences pinfo) (functions pinfo) agenda acc chart
+ chart2 = chart1{ active =emptyAC
+ , actives=active chart1 : actives chart1
+ , passive=emptyPC
+ , offset =offset chart1+1
+ }
+ in if TMap.null acc1
+ then Left (EState pgf pinfo chart2)
+ else Right (PState pgf pinfo chart2 acc1)
+ where
+ add (tok:toks) item acc
+ | tok == t = TMap.insertWith Set.union toks (Set.singleton item) acc
+ add _ item acc = acc
+
+-- | If the next token is not known but only its prefix (possible empty prefix)
+-- then the 'getCompletions' function can be used to calculate the possible
+-- next words and the consequent states. This is used for word completions in
+-- the GF interpreter.
+getCompletions :: ParseState -> String -> Map.Map String ParseState
+getCompletions (PState pgf pinfo chart items) w =
+ let (mb_agenda,map_items) = TMap.decompose items
+ agenda = maybe [] Set.toList mb_agenda
+ acc = Map.filterWithKey (\tok _ -> isPrefixOf w tok) map_items
+ (acc',chart1) = process Nothing add (sequences pinfo) (functions pinfo) agenda acc chart
+ chart2 = chart1{ active =emptyAC
+ , actives=active chart1 : actives chart1
+ , passive=emptyPC
+ , offset =offset chart1+1
+ }
+ in fmap (PState pgf pinfo chart2) acc'
+ where
+ add (tok:toks) item acc
+ | isPrefixOf w tok = Map.insertWith (TMap.unionWith Set.union) tok (TMap.singleton toks (Set.singleton item)) acc
+ add _ item acc = acc
+
+recoveryStates :: [Type] -> ErrorState -> (ParseState, Map.Map String ParseState)
+recoveryStates open_types (EState pgf pinfo chart) =
+ let open_fcats = concatMap type2fcats open_types
+ agenda = foldl (complete open_fcats) [] (actives chart)
+ (acc,chart1) = process Nothing add (sequences pinfo) (functions pinfo) agenda Map.empty chart
+ chart2 = chart1{ active =emptyAC
+ , actives=active chart1 : actives chart1
+ , passive=emptyPC
+ , offset =offset chart1+1
+ }
+ in (PState pgf pinfo chart (TMap.singleton [] (Set.fromList agenda)), fmap (PState pgf pinfo chart2) acc)
+ where
+ type2fcats (DTyp _ cat _) = maybe [] range (Map.lookup cat (startCats pinfo))
+
+ complete open_fcats items ac =
+ foldl (Set.fold (\(Active j' ppos funid seqid args keyc) ->
+ (:) (Active j' (ppos+1) funid seqid args keyc)))
+ items
+ [set | fcat <- open_fcats, set <- lookupACByFCat fcat ac]
+
+ add (tok:toks) item acc = Map.insertWith (TMap.unionWith Set.union) tok (TMap.singleton toks (Set.singleton item)) acc
+
+-- | This function extracts the list of all completed parse trees
+-- that spans the whole input consumed so far. The trees are also
+-- limited by the category specified, which is usually
+-- the same as the startup category.
+extractTrees :: ParseState -> Type -> [Tree]
+extractTrees (PState pgf pinfo chart items) ty@(DTyp _ start _) =
+ nubsort [e1 | e <- exps, Right e1 <- [checkExpr pgf e ty]]
+ where
+ (mb_agenda,acc) = TMap.decompose items
+ agenda = maybe [] Set.toList mb_agenda
+ (_,st) = process Nothing (\_ _ -> id) (sequences pinfo) (functions pinfo) agenda () chart
+
+ exps = do
+ cat <- maybe [] range (Map.lookup start (startCats pinfo))
+ (funid,args) <- foldForest (\funid args -> (:) (funid,args)) (\_ _ args -> args)
+ [] cat (productions pinfo)
+ let FFun fn lins = functions pinfo ! funid
+ lbl <- indices lins
+ Just fid <- [lookupPC (PK cat lbl 0) (passive st)]
+ (fvs,tree) <- go Set.empty 0 (0,fid)
+ guard (Set.null fvs)
+ return tree
+
+ go rec fcat' (d,fcat)
+ | fcat < totalCats pinfo = return (Set.empty,EMeta (fcat'*10+d)) -- FIXME: here we assume that every rule has at most 10 arguments
+ | Set.member fcat rec = mzero
+ | otherwise = foldForest (\funid args trees ->
+ do let FFun fn lins = functions pinfo ! funid
+ args <- mapM (go (Set.insert fcat rec) fcat) (zip [0..] args)
+ check_ho_fun fn args
+ `mplus`
+ trees)
+ (\const _ trees ->
+ return (freeVar const,const)
+ `mplus`
+ trees)
+ [] fcat (forest st)
+
+ check_ho_fun fun args
+ | fun == _V = return (head args)
+ | fun == _B = return (foldl1 Set.difference (map fst args), foldr (\x e -> EAbs Explicit (mkVar (snd x)) e) (snd (head args)) (tail args))
+ | otherwise = return (Set.unions (map fst args),foldl (\e x -> EApp e (snd x)) (EFun fun) args)
+
+ mkVar (EFun v) = v
+ mkVar (EMeta _) = wildCId
+
+ freeVar (EFun v) = Set.singleton v
+ freeVar _ = Set.empty
+
+_B = mkCId "_B"
+_V = mkCId "_V"
+
+process mbt fn !seqs !funs [] acc chart = (acc,chart)
+process mbt fn !seqs !funs (item@(Active j ppos funid seqid args key0):items) acc chart
+ | inRange (bounds lin) ppos =
+ case unsafeAt lin ppos of
+ FSymCat d r -> let !fid = args !! d
+ key = AK fid r
+
+ items2 = case lookupPC (mkPK key k) (passive chart) of
+ Nothing -> items
+ Just id -> (Active j (ppos+1) funid seqid (updateAt d id args) key0) : items
+ items3 = foldForest (\funid args items -> Active k 0 funid (rhs funid r) args key : items)
+ (\_ _ items -> items)
+ items2 fid (forest chart)
+ in case lookupAC key (active chart) of
+ Nothing -> process mbt fn seqs funs items3 acc chart{active=insertAC key (Set.singleton item) (active chart)}
+ Just set | Set.member item set -> process mbt fn seqs funs items acc chart
+ | otherwise -> process mbt fn seqs funs items2 acc chart{active=insertAC key (Set.insert item set) (active chart)}
+ FSymKS toks -> let !acc' = fn toks (Active j (ppos+1) funid seqid args key0) acc
+ in process mbt fn seqs funs items acc' chart
+ FSymKP strs vars
+ -> let !acc' = foldl (\acc toks -> fn toks (Active j (ppos+1) funid seqid args key0) acc) acc
+ (strs:[strs' | Alt strs' _ <- vars])
+ in process mbt fn seqs funs items acc' chart
+ FSymLit d r -> let !fid = args !! d
+ in case [ts | FConst _ ts <- maybe [] Set.toList (IntMap.lookup fid (forest chart))] of
+ (toks:_) -> let !acc' = fn toks (Active j (ppos+1) funid seqid args key0) acc
+ in process mbt fn seqs funs items acc' chart
+ [] -> case litCatMatch fid mbt of
+ Just (toks,lit) -> let fid' = nextId chart
+ !acc' = fn toks (Active j (ppos+1) funid seqid (updateAt d fid' args) key0) acc
+ in process mbt fn seqs funs items acc' chart{forest=IntMap.insert fid' (Set.singleton (FConst lit toks)) (forest chart)
+ ,nextId=nextId chart+1
+ }
+ Nothing -> process mbt fn seqs funs items acc chart
+ | otherwise =
+ case lookupPC (mkPK key0 j) (passive chart) of
+ Nothing -> let fid = nextId chart
+
+ items2 = case lookupAC key0 ((active chart:actives chart) !! (k-j)) of
+ Nothing -> items
+ Just set -> Set.fold (\(Active j' ppos funid seqid args keyc) ->
+ let FSymCat d _ = unsafeAt (unsafeAt seqs seqid) ppos
+ in (:) (Active j' (ppos+1) funid seqid (updateAt d fid args) keyc)) items set
+ in process mbt fn seqs funs items2 acc chart{passive=insertPC (mkPK key0 j) fid (passive chart)
+ ,forest =IntMap.insert fid (Set.singleton (FApply funid args)) (forest chart)
+ ,nextId =nextId chart+1
+ }
+ Just id -> let items2 = [Active k 0 funid (rhs funid r) args (AK id r) | r <- labelsAC id (active chart)] ++ items
+ in process mbt fn seqs funs items2 acc chart{forest = IntMap.insertWith Set.union id (Set.singleton (FApply funid args)) (forest chart)}
+ where
+ !lin = unsafeAt seqs seqid
+ !k = offset chart
+
+ mkPK (AK fid lbl) j = PK fid lbl j
+
+ rhs funid lbl = unsafeAt lins lbl
+ where
+ FFun _ lins = unsafeAt funs funid
+
+
+updateAt :: Int -> a -> [a] -> [a]
+updateAt nr x xs = [if i == nr then x else y | (i,y) <- zip [0..] xs]
+
+litCatMatch fcat (Just t)
+ | fcat == fcatString = Just ([t],ELit (LStr t))
+ | fcat == fcatInt = case reads t of {[(n,"")] -> Just ([t],ELit (LInt n));
+ _ -> Nothing }
+ | fcat == fcatFloat = case reads t of {[(d,"")] -> Just ([t],ELit (LFlt d));
+ _ -> Nothing }
+ | fcat == fcatVar = Just ([t],EFun (mkCId t))
+litCatMatch _ _ = Nothing
+
+
+----------------------------------------------------------------
+-- Active Chart
+----------------------------------------------------------------
+
+data Active
+ = Active {-# UNPACK #-} !Int
+ {-# UNPACK #-} !FPointPos
+ {-# UNPACK #-} !FunId
+ {-# UNPACK #-} !SeqId
+ [FCat]
+ {-# UNPACK #-} !ActiveKey
+ deriving (Eq,Show,Ord)
+data ActiveKey
+ = AK {-# UNPACK #-} !FCat
+ {-# UNPACK #-} !FIndex
+ deriving (Eq,Ord,Show)
+type ActiveChart = IntMap.IntMap (IntMap.IntMap (Set.Set Active))
+
+emptyAC :: ActiveChart
+emptyAC = IntMap.empty
+
+lookupAC :: ActiveKey -> ActiveChart -> Maybe (Set.Set Active)
+lookupAC (AK fcat l) chart = IntMap.lookup fcat chart >>= IntMap.lookup l
+
+lookupACByFCat :: FCat -> ActiveChart -> [Set.Set Active]
+lookupACByFCat fcat chart =
+ case IntMap.lookup fcat chart of
+ Nothing -> []
+ Just map -> IntMap.elems map
+
+labelsAC :: FCat -> ActiveChart -> [FIndex]
+labelsAC fcat chart =
+ case IntMap.lookup fcat chart of
+ Nothing -> []
+ Just map -> IntMap.keys map
+
+insertAC :: ActiveKey -> Set.Set Active -> ActiveChart -> ActiveChart
+insertAC (AK fcat l) set chart = IntMap.insertWith IntMap.union fcat (IntMap.singleton l set) chart
+
+
+----------------------------------------------------------------
+-- Passive Chart
+----------------------------------------------------------------
+
+data PassiveKey
+ = PK {-# UNPACK #-} !FCat
+ {-# UNPACK #-} !FIndex
+ {-# UNPACK #-} !Int
+ deriving (Eq,Ord,Show)
+
+type PassiveChart = Map.Map PassiveKey FCat
+
+emptyPC :: PassiveChart
+emptyPC = Map.empty
+
+lookupPC :: PassiveKey -> PassiveChart -> Maybe FCat
+lookupPC key chart = Map.lookup key chart
+
+insertPC :: PassiveKey -> FCat -> PassiveChart -> PassiveChart
+insertPC key fcat chart = Map.insert key fcat chart
+
+
+----------------------------------------------------------------
+-- Forest
+----------------------------------------------------------------
+
+foldForest :: (FunId -> [FCat] -> b -> b) -> (Expr -> [String] -> b -> b) -> b -> FCat -> IntMap.IntMap (Set.Set Production) -> b
+foldForest f g b fcat forest =
+ case IntMap.lookup fcat forest of
+ Nothing -> b
+ Just set -> Set.fold foldProd b set
+ where
+ foldProd (FCoerce fcat) b = foldForest f g b fcat forest
+ foldProd (FApply funid args) b = f funid args b
+ foldProd (FConst const toks) b = g const toks b
+
+
+----------------------------------------------------------------
+-- Parse State
+----------------------------------------------------------------
+
+-- | An abstract data type whose values represent
+-- the current state in an incremental parser.
+data ParseState = PState PGF ParserInfo Chart (TMap.TrieMap String (Set.Set Active))
+
+data Chart
+ = Chart
+ { active :: ActiveChart
+ , actives :: [ActiveChart]
+ , passive :: PassiveChart
+ , forest :: IntMap.IntMap (Set.Set Production)
+ , nextId :: {-# UNPACK #-} !FCat
+ , offset :: {-# UNPACK #-} !Int
+ }
+ deriving Show
+
+----------------------------------------------------------------
+-- Error State
+----------------------------------------------------------------
+
+-- | An abstract data type whose values represent
+-- the state in an incremental parser after an error.
+data ErrorState = EState PGF ParserInfo Chart
|