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d59749c9149a10a33ffae5e435337c8fe97f1699
gf-core/src/runtime/haskell/PGF/Parse.hs
john.j.camilleri d59749c914 PGF Web Service: include entire completion in full mode 
When using full=yes in the web service 'complete' command,
you now get an additional field 'seq' with the longest possible completion.
So, given:

  lin
    f1 = ss "the" ;
    f2 = ss ("the red house" | "the real deal") ;

and trying to complete on input "th", you get:

    [
        {
            "from": "TestCnc",
            "brackets": {
                "cat": "_",
                "fid": 0,
                "index": 0,
                "fun": "_",
                "children": []
            },
            "text": "th",
            "completions": [
                {
                    "token": "the",
                    "funs": [
                        {
                            "fun": "f1",
                            "hyps": [],
                            "cat": "C",
                            "seq": "the"
                        },
                        {
                            "fun": "f2",
                            "hyps": [],
                            "cat": "C",
                            "seq": "the red house"
                        },
                        {
                            "fun": "f2",
                            "hyps": [],
                            "cat": "C",
                            "seq": "the real deal"
                        }
                    ]
                }
            ]
        }
    ]
2014-07-15 09:33:22 +00:00

537 lines
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{-# LANGUAGE BangPatterns, RankNTypes #-}
module PGF.Parse
( ParseState
, ErrorState
, initState
, nextState
, getCompletions
, recoveryStates
, ParseInput(..), simpleParseInput, mkParseInput
, ParseOutput(..), getParseOutput
, parse
, parseWithRecovery
, getContinuationInfo
) where
import Data.Array.IArray
import Data.Array.Base (unsafeAt)
import Data.List (isPrefixOf, foldl', intercalate)
import Data.Maybe (fromMaybe, maybeToList)
import qualified Data.Map as Map
import qualified PGF.TrieMap as TrieMap
import qualified Data.IntMap as IntMap
import qualified Data.IntSet as IntSet
import qualified Data.Set as Set
import Control.Monad
import PGF.CId
import PGF.Data
import PGF.Expr(Tree)
import PGF.Macros
import PGF.TypeCheck
import PGF.Forest(Forest(Forest), linearizeWithBrackets, getAbsTrees)
-- | The input to the parser is a pair of predicates. The first one
-- 'piToken' selects a token from a list of suggestions from the grammar,
-- actually appears at the current position in the input string.
-- The second one 'piLiteral' recognizes whether a literal with forest id 'FId'
-- could be matched at the current position.
data ParseInput
= ParseInput
{ piToken :: forall a . Map.Map Token a -> Maybe a
, piLiteral :: FId -> Maybe (CId,Tree,[Token])
}
-- | This data type encodes the different outcomes which you could get from the parser.
data ParseOutput
= ParseFailed Int -- ^ The integer is the position in number of tokens where the parser failed.
| TypeError [(FId,TcError)] -- ^ The parsing was successful but none of the trees is type correct.
-- The forest id ('FId') points to the bracketed string from the parser
-- where the type checking failed. More than one error is returned
-- if there are many analizes for some phrase but they all are not type correct.
| ParseOk [Tree] -- ^ If the parsing and the type checking are successful we get a list of abstract syntax trees.
-- The list should be non-empty.
| ParseIncomplete -- ^ The sentence is not complete. Only partial output is produced
parse :: PGF -> Language -> Type -> Maybe Int -> [Token] -> (ParseOutput,BracketedString)
parse pgf lang typ dp toks = loop (initState pgf lang typ) toks
where
loop ps [] = getParseOutput ps typ dp
loop ps (t:ts) = case nextState ps (simpleParseInput t) of
Left es -> case es of
EState _ _ chart -> (ParseFailed (offset chart),snd (getParseOutput ps typ dp))
Right ps -> loop ps ts
parseWithRecovery :: PGF -> Language -> Type -> [Type] -> Maybe Int -> [String] -> (ParseOutput,BracketedString)
parseWithRecovery pgf lang typ open_typs dp toks = accept (initState pgf lang typ) toks
where
accept ps [] = getParseOutput ps typ dp
accept ps (t:ts) =
case nextState ps (simpleParseInput t) of
Right ps -> accept ps ts
Left es -> skip (recoveryStates open_typs es) ts
skip ps_map [] = getParseOutput (fst ps_map) typ dp
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 (acc,items) = case Map.lookup start (cnccats cnc) of
Just (CncCat s e labels) ->
let keys = do fid <- range (s,e)
lbl <- indices labels
return (AK fid lbl)
in foldl' (\(acc,items) key -> predict flit ftok cnc
(pproductions cnc)
key key 0
acc items)
(Map.empty,[])
keys
Nothing -> (Map.empty,[])
in PState abs
cnc
(Chart emptyAC [] emptyPC (pproductions cnc) (totalCats cnc) 0)
(TrieMap.compose (Just (Set.fromList items)) acc)
where
abs = abstract pgf
cnc = lookConcrComplete pgf lang
flit _ = Nothing
ftok = Map.unionWith (TrieMap.unionWith Set.union)
-- | This function constructs the simplest possible parser input.
-- It checks the tokens for exact matching and recognizes only @String@, @Int@ and @Float@ literals.
-- The @Int@ and @Float@ literals match only if the token passed is some number.
-- The @String@ literal always match but the length of the literal could be only one token.
simpleParseInput :: Token -> ParseInput
simpleParseInput t = ParseInput (Map.lookup t) (matchLit t)
where
matchLit t fid
| fid == fidString = Just (cidString,ELit (LStr t),[t])
| fid == fidInt = case reads t of {[(n,"")] -> Just (cidInt,ELit (LInt n),[t]);
_ -> Nothing }
| fid == fidFloat = case reads t of {[(d,"")] -> Just (cidFloat,ELit (LFlt d),[t]);
_ -> Nothing }
| fid == fidVar = Just (wildCId,EFun (mkCId t),[t])
| otherwise = Nothing
mkParseInput :: PGF -> Language
-> (forall a . b -> Map.Map Token a -> Maybe a)
-> [(CId,b -> Maybe (Tree,[Token]))]
-> (b -> ParseInput)
mkParseInput pgf lang ftok flits = \x -> ParseInput (ftok x) (flit x)
where
flit = mk flits
cnc = lookConcr pgf lang
mk [] = \x fid -> Nothing
mk ((c,flit):flits) = \x fid -> case Map.lookup c (cnccats cnc) of
Just (CncCat s e _) | inRange (s,e) fid
-> fmap (\(tree,toks) -> (c,tree,toks)) (flit x)
_ -> mk flits x fid
-- | 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 -> ParseInput -> Either ErrorState ParseState
nextState (PState abs cnc chart cnt0) input =
let (mb_agenda,map_items) = TrieMap.decompose cnt0
agenda = maybe [] Set.toList mb_agenda
cnt = fromMaybe TrieMap.empty (piToken input map_items)
(cnt1,chart1) = process flit ftok cnc agenda cnt chart
chart2 = chart1{ active =emptyAC
, actives=active chart1 : actives chart1
, passive=emptyPC
, offset =offset chart1+1
}
in if TrieMap.null cnt1
then Left (EState abs cnc chart2)
else Right (PState abs cnc chart2 cnt1)
where
flit = piLiteral input
ftok choices cnt =
case piToken input choices of
Just cnt' -> TrieMap.unionWith Set.union cnt' cnt
Nothing -> cnt
-- | 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 Token ParseState
getCompletions (PState abs cnc chart cnt0) w =
let (mb_agenda,map_items) = TrieMap.decompose cnt0
agenda = maybe [] Set.toList mb_agenda
acc = Map.filterWithKey (\tok _ -> isPrefixOf w tok) map_items
(acc',chart1) = process flit ftok cnc agenda acc chart
chart2 = chart1{ active =emptyAC
, actives=active chart1 : actives chart1
, passive=emptyPC
, offset =offset chart1+1
}
in fmap (PState abs cnc chart2) acc'
where
flit _ = Nothing
ftok choices =
Map.unionWith (TrieMap.unionWith Set.union)
(Map.filterWithKey (\tok _ -> isPrefixOf w tok) choices)
recoveryStates :: [Type] -> ErrorState -> (ParseState, Map.Map Token ParseState)
recoveryStates open_types (EState abs cnc chart) =
let open_fcats = concatMap type2fcats open_types
agenda = foldl (complete open_fcats) [] (actives chart)
(acc,chart1) = process flit ftok cnc agenda Map.empty chart
chart2 = chart1{ active =emptyAC
, actives=active chart1 : actives chart1
, passive=emptyPC
, offset =offset chart1+1
}
in (PState abs cnc chart (TrieMap.singleton [] (Set.fromList agenda)), fmap (PState abs cnc chart2) acc)
where
type2fcats (DTyp _ cat _) = case Map.lookup cat (cnccats cnc) of
Just (CncCat s e labels) -> range (s,e)
Nothing -> []
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]
flit _ = Nothing
ftok toks = Map.unionWith (TrieMap.unionWith Set.union) toks
-- | 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.
getParseOutput :: ParseState -> Type -> Maybe Int -> (ParseOutput,BracketedString)
getParseOutput (PState abs cnc chart cnt) ty@(DTyp _ start _) dp =
let froots | null roots = getPartialSeq (sequences cnc) (reverse (active chart1 : actives chart1)) seq
| otherwise = [([SymCat 0 lbl],[PArg [] fid]) | AK fid lbl <- roots]
f = Forest abs cnc (forest chart1) froots
bs = linearizeWithBrackets dp f
res | not (null es) = ParseOk es
| not (null errs) = TypeError errs
| otherwise = ParseIncomplete
where xs = [getAbsTrees f (PArg [] fid) (Just ty) dp | (AK fid lbl) <- roots]
es = concat [es | Right es <- xs]
errs = concat [errs | Left errs <- xs]
in (res,bs)
where
(mb_agenda,acc) = TrieMap.decompose cnt
agenda = maybe [] Set.toList mb_agenda
(acc',chart1) = process flit ftok cnc agenda (TrieMap.compose Nothing acc) chart
seq = [(j,cutAt ppos toks seqid,args,key) | (toks,set) <- TrieMap.toList acc'
, Active j ppos funid seqid args key <- Set.toList set]
flit _ = Nothing
ftok toks = TrieMap.unionWith Set.union (TrieMap.compose Nothing toks)
cutAt ppos toks seqid =
let seq = unsafeAt (sequences cnc) seqid
init = take (ppos-1) (elems seq)
tail = case unsafeAt seq (ppos-1) of
SymKS t -> drop (length toks) [SymKS t]
SymKP ts _ -> reverse (drop (length toks) (reverse ts))
sym -> []
in init ++ tail
roots = case Map.lookup start (cnccats cnc) of
Just (CncCat s e lbls) -> do cat <- range (s,e)
lbl <- indices lbls
fid <- maybeToList (lookupPC (PK cat lbl 0) (passive chart1))
return (AK fid lbl)
Nothing -> mzero
getPartialSeq seqs actives = expand Set.empty
where
expand acc [] =
[(lin,args) | (j,lin,args,key) <- Set.toList acc, j == 0]
expand acc (item@(j,lin,args,key) : items)
| item `Set.member` acc = expand acc items
| otherwise = expand acc' items'
where
acc' = Set.insert item acc
items' = case lookupAC key (actives !! j) of
Nothing -> items
Just (set,_) -> [if j' < j
then let lin' = take ppos (elems (unsafeAt seqs seqid))
in (j',lin'++map (inc (length args')) lin,args'++args,key')
else (j',lin,args,key') | Active j' ppos funid seqid args' key' <- Set.toList set] ++ items
inc n (SymCat d r) = SymCat (n+d) r
inc n (SymVar d r) = SymVar (n+d) r
inc n (SymLit d r) = SymLit (n+d) r
inc n s = s
process flit ftok cnc [] acc chart = (acc,chart)
process flit ftok cnc (item@(Active j ppos funid seqid args key0):items) acc chart
| inRange (bounds lin) ppos =
case unsafeAt lin ppos of
SymCat d r -> let PArg hypos !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 (PArg hypos id) args) key0) : items
(acc',items4) = predict flit ftok cnc
(IntMap.unionWith Set.union new_sc (forest chart))
key key k
acc items2
new_sc = foldl uu parent_sc hypos
parent_sc = case lookupAC key0 ((active chart : actives chart) !! (k-j)) of
Nothing -> IntMap.empty
Just (set,sc) -> sc
in case lookupAC key (active chart) of
Nothing -> process flit ftok cnc items4 acc' chart{active=insertAC key (Set.singleton item,new_sc) (active chart)}
Just (set,sc) | Set.member item set -> process flit ftok cnc items acc chart
| otherwise -> process flit ftok cnc items2 acc chart{active=insertAC key (Set.insert item set,IntMap.unionWith Set.union new_sc sc) (active chart)}
SymKS tok -> let !acc' = ftok_ [tok] (Active j (ppos+1) funid seqid args key0) acc
in process flit ftok cnc items acc' chart
SymNE -> process flit ftok cnc items acc chart
SymBIND -> let !acc' = ftok_ ["&+"] (Active j (ppos+1) funid seqid args key0) acc
in process flit ftok cnc items acc' chart
SymSOFT_BIND->process flit ftok cnc ((Active j (ppos+1) funid seqid args key0):items) acc chart
SymKP syms vars
-> let to_tok (SymKS t) = [t]
to_tok SymBIND = ["&+"]
to_tok SymSOFT_BIND = []
to_tok _ = []
!acc' = foldl (\acc syms -> ftok_ (concatMap to_tok syms) (Active j (ppos+1) funid seqid args key0) acc) acc
(syms:[syms' | (syms',_) <- vars])
in process flit ftok cnc items acc' chart
SymLit d r -> let PArg hypos fid = args !! d
key = AK fid r
!fid' = case lookupPC (mkPK key k) (passive chart) of
Nothing -> fid
Just fid -> fid
in case [ts | PConst _ _ ts <- maybe [] Set.toList (IntMap.lookup fid' (forest chart))] of
(toks:_) -> let !acc' = ftok_ toks (Active j (ppos+1) funid seqid (updateAt d (PArg hypos fid') args) key0) acc
in process flit ftok cnc items acc' chart
[] -> case flit fid of
Just (cat,lit,toks)
-> let fid' = nextId chart
!acc' = ftok_ toks (Active j (ppos+1) funid seqid (updateAt d (PArg hypos fid') args) key0) acc
in process flit ftok cnc items acc' chart{passive=insertPC (mkPK key k) fid' (passive chart)
,forest =IntMap.insert fid' (Set.singleton (PConst cat lit toks)) (forest chart)
,nextId =nextId chart+1
}
Nothing -> process flit ftok cnc items acc chart
SymVar d r -> let PArg hypos fid0 = args !! d
(fid1,fid2) = hypos !! r
key = AK fid1 0
!fid' = case lookupPC (mkPK key k) (passive chart) of
Nothing -> fid1
Just fid -> fid
in case [ts | PConst _ _ ts <- maybe [] Set.toList (IntMap.lookup fid' (forest chart))] of
(toks:_) -> let !acc' = ftok_ toks (Active j (ppos+1) funid seqid (updateAt d (PArg (updateAt r (fid',fid2) hypos) fid0) args) key0) acc
in process flit ftok cnc items acc' chart
[] -> case flit fid1 of
Just (cat,lit,toks)
-> let fid' = nextId chart
!acc' = ftok_ toks (Active j (ppos+1) funid seqid (updateAt d (PArg (updateAt r (fid',fid2) hypos) fid0) args) key0) acc
in process flit ftok cnc items acc' chart{passive=insertPC (mkPK key k) fid' (passive chart)
,forest =IntMap.insert fid' (Set.singleton (PConst cat lit toks)) (forest chart)
,nextId =nextId chart+1
}
Nothing -> process flit ftok cnc 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,sc) -> Set.fold (\(Active j' ppos funid seqid args keyc) ->
let SymCat d _ = unsafeAt (unsafeAt (sequences cnc) seqid) ppos
PArg hypos _ = args !! d
in (:) (Active j' (ppos+1) funid seqid (updateAt d (PArg hypos fid) args) keyc)) items set
in process flit ftok cnc items2 acc chart{passive=insertPC (mkPK key0 j) fid (passive chart)
,forest =IntMap.insert fid (Set.singleton (PApply 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 flit ftok cnc items2 acc chart{forest = IntMap.insertWith Set.union id (Set.singleton (PApply funid args)) (forest chart)}
where
!lin = unsafeAt (sequences cnc) seqid
!k = offset chart
mkPK (AK fid lbl) j = PK fid lbl j
rhs funid lbl = unsafeAt lins lbl
where
CncFun _ lins = unsafeAt (cncfuns cnc) funid
uu forest (fid1,fid2) =
case IntMap.lookup fid2 (lindefs cnc) of
Just funs -> foldl (\forest funid -> IntMap.insertWith Set.union fid2 (Set.singleton (PApply funid [PArg [] fid1])) forest) forest funs
Nothing -> forest
ftok_ [] item cnt = ftok Map.empty cnt
ftok_ (tok:toks) item cnt =
ftok (Map.singleton tok (TrieMap.singleton toks (Set.singleton item))) cnt
predict flit ftok cnc forest key0 key@(AK fid lbl) k acc items =
let (acc1,items1) = case IntMap.lookup fid forest of
Nothing -> (acc,items)
Just set -> Set.fold foldProd (acc,items) set
(acc2,items2) = case IntMap.lookup fid (lexicon cnc) >>= IntMap.lookup lbl of
Just tmap -> let (mb_v,toks) = TrieMap.decompose (TrieMap.map (toItems key0 k) tmap)
acc1' = ftok toks acc1
items1' = maybe [] Set.toList mb_v ++ items1
in (acc1',items1')
Nothing -> (acc1,items1)
in (acc2,items2)
where
foldProd (PCoerce fid) (acc,items) = predict flit ftok cnc forest key0 (AK fid lbl) k acc items
foldProd (PApply funid args) (acc,items) = (acc,Active k 0 funid (rhs funid lbl) args key0 : items)
foldProd (PConst _ const toks) (acc,items) = (acc,items)
rhs funid lbl = unsafeAt lins lbl
where
CncFun _ lins = unsafeAt (cncfuns cnc) funid
toItems key@(AK fid lbl) k funids =
Set.fromList [Active k 1 funid (rhs funid lbl) [] key | funid <- IntSet.toList funids]
updateAt :: Int -> a -> [a] -> [a]
updateAt nr x xs = [if i == nr then x else y | (i,y) <- zip [0..] xs]
----------------------------------------------------------------
-- Active Chart
----------------------------------------------------------------
data Active
= Active {-# UNPACK #-} !Int
{-# UNPACK #-} !DotPos
{-# UNPACK #-} !FunId
{-# UNPACK #-} !SeqId
[PArg]
{-# UNPACK #-} !ActiveKey
deriving (Eq,Show,Ord)
data ActiveKey
= AK {-# UNPACK #-} !FId
{-# UNPACK #-} !LIndex
deriving (Eq,Ord,Show)
type ActiveSet = Set.Set Active
type ActiveChart = IntMap.IntMap (IntMap.IntMap (ActiveSet, IntMap.IntMap (Set.Set Production)))
emptyAC :: ActiveChart
emptyAC = IntMap.empty
lookupAC :: ActiveKey -> ActiveChart -> Maybe (ActiveSet, IntMap.IntMap (Set.Set Production))
lookupAC (AK fid lbl) chart = IntMap.lookup fid chart >>= IntMap.lookup lbl
lookupACByFCat :: FId -> ActiveChart -> [(ActiveSet, IntMap.IntMap (Set.Set Production))]
lookupACByFCat fcat chart =
case IntMap.lookup fcat chart of
Nothing -> []
Just map -> IntMap.elems map
labelsAC :: FId -> ActiveChart -> [LIndex]
labelsAC fcat chart =
case IntMap.lookup fcat chart of
Nothing -> []
Just map -> IntMap.keys map
insertAC :: ActiveKey -> (ActiveSet, IntMap.IntMap (Set.Set Production)) -> ActiveChart -> ActiveChart
insertAC (AK fcat l) set chart = IntMap.insertWith IntMap.union fcat (IntMap.singleton l set) chart
----------------------------------------------------------------
-- Passive Chart
----------------------------------------------------------------
data PassiveKey
= PK {-# UNPACK #-} !FId
{-# UNPACK #-} !LIndex
{-# UNPACK #-} !Int
deriving (Eq,Ord,Show)
type PassiveChart = Map.Map PassiveKey FId
emptyPC :: PassiveChart
emptyPC = Map.empty
lookupPC :: PassiveKey -> PassiveChart -> Maybe FId
lookupPC key chart = Map.lookup key chart
insertPC :: PassiveKey -> FId -> PassiveChart -> PassiveChart
insertPC key fcat chart = Map.insert key fcat chart
----------------------------------------------------------------
-- Parse State
----------------------------------------------------------------
-- | An abstract data type whose values represent
-- the current state in an incremental parser.
data ParseState = PState Abstr Concr Chart Continuation
data Chart
= Chart
{ active :: ActiveChart
, actives :: [ActiveChart]
, passive :: PassiveChart
, forest :: IntMap.IntMap (Set.Set Production)
, nextId :: {-# UNPACK #-} !FId
, offset :: {-# UNPACK #-} !Int
}
deriving Show
type Continuation = TrieMap.TrieMap Token ActiveSet
-- | Return the Continuation of a Parsestate with exportable types
-- Used by PGFService
getContinuationInfo :: ParseState -> Map.Map [Token] [(FunId, CId, String)]
getContinuationInfo pstate = Map.map (map f . Set.toList) contMap
where
PState abstr concr chart cont = pstate
contMap = Map.fromList (TrieMap.toList cont) -- always get [([], _::ActiveSet)]
f :: Active -> (FunId,CId,String)
f (Active int dotpos funid seqid pargs ak) = (funid, cid, seq)
where
CncFun cid _ = cncfuns concr ! funid
seq = showSeq dotpos (sequences concr ! seqid)
showSeq :: DotPos -> Sequence -> String
showSeq pos seq = intercalate " " $ scan (drop (pos-1) (elems seq))
where
-- Scan left-to-right, stop at first non-token
scan :: [Symbol] -> [String]
scan [] = []
scan (sym:syms) = case sym of
SymKS token -> token : scan syms
_ -> []
----------------------------------------------------------------
-- Error State
----------------------------------------------------------------
-- | An abstract data type whose values represent
-- the state in an incremental parser after an error.
data ErrorState = EState Abstr Concr Chart
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