{- |

Module : $Header$

Copyright : (c) Christian Maeder and Uni Bremen 2003

Licence : All rights reserved.

Maintainer : hets@tzi.de

Stability : experimental

Portability : portable

Mixfix analysis of terms and patterns, adapted from the CASL analysis

-}

module HasCASL.MixAna where

import Common.GlobalAnnotations

import Common.Result

import Common.Id

import Common.PrettyPrint

import qualified Common.Lib.Map as Map

import qualified Common.Lib.Set as Set

import Common.Lib.State

import HasCASL.As

import HasCASL.Le

import HasCASL.Unify

import HasCASL.ClassAna

import HasCASL.TypeAna

import HasCASL.VarDecl

import HasCASL.MixParserState

import Data.Maybe

-- import Debug.Trace

-- Earley Algorithm

lookUp :: (Ord a) => Map.Map a [b] -> a -> [b]

lookUp ce k = Map.findWithDefault [] k ce

type PMap a = Map.Map Index [PState a]

data ParseMap a = ParseMap { lastIndex :: Index

, parseMap :: PMap a

}

termToToken :: Term -> Token

termToToken trm =

case trm of

TermToken x -> x

TypedTerm _ _ _ _ -> inTok

_ -> opTok

-- match (and shift) a token (or partially finished term)

scan :: TypeMap -> Knowns -> (Maybe Type, a) -> (a -> Token)

-> State (Int, ParseMap a) ()

scan tm knowns (ty, trm) f =

do (c, pm) <- get

let m = parseMap pm

i = lastIndex pm

incI = incrIndex i

(ps, c2) = runState (mapM (scanState tm knowns (ty, trm)

$ f trm) $ lookUp m i) c

put (c2, pm { lastIndex = incI,

parseMap = Map.insert incI (concat ps) m })

-- final complete/reduction phase

-- when a grammar rule (mixfix Id) has been fully matched

collectArg :: GlobalAnnos -> TypeMap -> PMap a -> (PState a -> a)

-> PState a -> [PState a]

-- pre: finished rule

collectArg ga tm m f

s@(PState { ruleId = argIde, stateNo = arg, ruleType = argType }) =

map (\ p -> p { restRule = tail $ restRule p })

$ mapMaybe (filterByType tm (argType, f s))

$ filter (filterByPrec ga argIde)

$ lookUp m arg

compl :: GlobalAnnos -> TypeMap -> PMap a -> (PState a -> a)

-> [PState a] -> [PState a]

compl ga tm m f l =

concat $ map (collectArg ga tm m f)

$ filter (null . restRule) l

complRec :: GlobalAnnos -> TypeMap -> PMap a -> (PState a -> a)

-> [PState a] -> [PState a]

complRec ga tm m f l = let l1 = compl ga tm m f l in

if null l1 then l else complRec ga tm m f l1 ++ l

complete :: GlobalAnnos -> TypeMap -> (PState a -> a) -> State (ParseMap a) ()

complete ga tm f =

do pm <- get

let m = parseMap pm

i = lastIndex pm

put pm { parseMap = Map.insert i

(complRec ga tm m f $ lookUp m i) m }

-- predict which rules/ids might match for (the) nonterminal(s) (termTok)

-- provided the "dot" is followed by a nonterminal

predict :: (Index -> State Int [PState a]) -> State (Int, ParseMap a) ()

predict f =

do (c, pm) <- get

let m = parseMap pm

i = lastIndex pm

if not (isStartIndex i) && any (\ (PState { restRule = ts }) ->

not (null ts) && head ts == termTok)

(lookUp m i)

then let (nextStates, c2) = runState (f i) c

in put (c2,

pm { parseMap = Map.insertWith (++) i

nextStates m })

else return ()

addDiag :: Diagnosis -> State (Env, ParseMap a) ()

addDiag d = do (e, pm) <- get

put (e { envDiags = d : envDiags e}, pm)

completeScanPredict :: (PrettyPrint a, PosItem a)

=> GlobalAnnos -> Knowns

-> (Maybe Type, a) -> (PState a -> a) -> (a -> Token)

-> (Index -> State Int [PState a])

-> State (Env, ParseMap a) ()

completeScanPredict ga knowns (ty, a) fromState toToken initStates =

do (e, pm0) <- get

let tm = typeMap e

(c, pm1) = execState (do predict initStates

scan tm knowns (ty, a) toToken)

(counter e, pm0)

pm2 = execState (complete ga tm fromState) pm1

put (e { counter = c }, pm2)

let m = parseMap pm2

i = lastIndex pm2

if (null $ lookUp m i) && (not $ null $ lookUp m $ decrIndex i)

then addDiag $ mkDiag Error "unexpected mixfix token" a

else return ()

nextState :: GlobalAnnos -> (Maybe Type, Term) -> State (Env, ParseMap Term) ()

nextState ga (ty, trm) =

do e <- gets fst

completeScanPredict ga Set.empty (ty, trm)

stateToAppl termToToken $ initialState ga $ assumps e

-- | find information for qualified operation

findOpId :: Assumps -> TypeMap -> Int -> UninstOpId -> Type -> Maybe OpInfo

findOpId as tm c i ty = listToMaybe $ fst $

partitionOpId as tm c i $ TypeScheme [] ([] :=> ty) []

filterOps :: Assumps -> Assumps

filterOps = filterAssumps ( \ o -> case opDefn o of

ConstructData _ -> True

VarDefn -> True

_ -> False)

iterStates :: GlobalAnnos -> Type -> [Term]

-> State (Env, ParseMap Term) ()

iterStates ga ty terms =

do (e, pm) <- get

let self = iterStates ga ty

as = assumps e

tm = typeMap e

c = counter e

if null terms then return () else case head terms of

MixfixTerm ts -> self (ts ++ tail terms)

BracketTerm b ts ps -> self

(expandPos TermToken (getBrackets b) ts ps ++ tail terms)

QualVar v typ ps ->

do let (mTyp, e2) = runState (anaStarType typ) e

put (e2, pm)

case mTyp of

Nothing -> return ()

Just nTyp -> do

let mi = findOpId as tm c v nTyp

case mi of

Nothing -> addDiag $ mkDiag Error

"value not found" v

Just _ -> do

nextState ga (Just nTyp, QualVar v nTyp ps)

self (tail terms)

QualOp io@(InstOpId v _ _) (TypeScheme rs (qs :=> typ) ss) ps ->

do let (mTyp, e2) = runState (anaStarType typ) e

put (e2, pm)

case mTyp of

Nothing -> return ()

Just nTyp -> do

let mi = findOpId as tm c v nTyp

case mi of

Nothing -> addDiag $ mkDiag Error

"value not found" v

Just _ -> do

nextState ga (Just nTyp, QualOp io

(TypeScheme rs (qs :=> nTyp) ss) ps)

self (tail terms)

TypedTerm hd tqual typ ps ->

do let (mTyp, e1) = runState (anaStarType typ) e

(mtt, e2) = runState

(case tqual of

OfType -> case mTyp of

Nothing -> resolveAny ga hd

Just nTyp -> resolve ga (nTyp, hd)

_ -> resolveAny ga hd) e1

put (e2, pm)

case mtt of

Just (_, ttt) ->

do case mTyp of

Nothing -> return ()

Just nTyp -> do

nextState ga (case tqual of

InType -> Just logicalType

_ -> mTyp,

TypedTerm ttt tqual nTyp ps)

self (tail terms)

Nothing -> return ()

QuantifiedTerm quant decls hd ps ->

do let (mDecls, e1) = runState (mapM anaGenVarDecl decls) e

newDecls = catMaybes mDecls

let (mtt, e2) = runState (resolve ga (logicalType, hd)) e1

put (e2 { typeMap = tm, assumps = as }, pm)

case mtt of

Just (_, tt) ->

do nextState ga (Just logicalType,

QuantifiedTerm quant newDecls tt ps)

self (tail terms)

Nothing -> return ()

LambdaTerm decls part hd ps ->

do let (mDecls, e0) = runState (mapM (resolvePattern ga)

decls) e

{ assumps = filterOps as }

newDecls = map snd $ catMaybes mDecls

vDecls = concatMap extractBindings newDecls

(_, e1) = runState (mapM_ addVarDecl vDecls) e0

{ assumps = as }

let (mtt, e2) = runState (resolveAny ga hd) e1

put (e2 {assumps = as}, pm)

case mtt of

Just (typ, tt) ->

do nextState ga (Just typ,

LambdaTerm newDecls part tt ps)

self (tail terms)

Nothing -> return ()

CaseTerm hd (ProgEq pat e1 pps : _) ps ->

do let (mtt, e2) = runState (resolveAny ga hd) e

(frst, e3) = runState

(resolveAny ga e1) e2

put (e3, pm)

case (mtt, frst) of

(Just (_, tt), Just (typ, te)) ->

do nextState ga (Just typ,

CaseTerm tt [ProgEq pat te pps] ps)

self (tail terms)

_ -> return ()

LetTerm eqs hd ps ->

do let (mtt, e2) = runState

(resolveAny ga hd) e

put (e2, pm)

case mtt of

Just (typq, tt) ->

do nextState ga (Just typq, LetTerm eqs tt ps)

self (tail terms)

Nothing -> return ()

t@(TermToken _) -> do nextState ga (Nothing, t)

self (tail terms)

t -> error ("iterStates: " ++ show t)

getAppls :: ParseMap a -> [PState a]

getAppls pm =

filter (\ (PState { restRule = ts, stateNo = k })

-> null ts && isStartIndex k) $

lookUp (parseMap pm) $ lastIndex pm

getLastType :: ParseMap a -> Type

getLastType pm =

let tys = map ruleType $

filter (\ (PState { restRule = ts, stateNo = k })

-> null ts && isStartIndex k) $

lookUp (parseMap pm) $ lastIndex pm

in if null tys then error "getLastType" else head tys

resolveToParseMap :: GlobalAnnos -> Type -> Term -> State Env (ParseMap Term)

resolveToParseMap ga ty trm =

do as <- gets assumps

initStates <- toEnvState (initialState ga as startIndex)

let pm = ParseMap { lastIndex = startIndex

, parseMap = Map.single startIndex initStates }

e <- get

let (e2, pm2) = execState (iterStates ga ty [trm]) (e, pm)

put e2

return pm2

checkResultType :: TypeMap -> Type -> ParseMap a -> ParseMap a

checkResultType tm t pm =

let m = parseMap pm

i = lastIndex pm in

pm { parseMap = Map.insert i

(mapMaybe (filterByResultType tm t)

$ lookUp m i) m }

resolveFromParseMap :: (PosItem a, PrettyPrint a) => (PState a -> a)

-> (Type, a) -> ParseMap a -> State Env (Maybe (Type, a))

resolveFromParseMap f (ty, a) pm0 =

do tm <- gets typeMap

let i = lastIndex pm0

pm = checkResultType tm ty pm0

ts = map f $ getAppls pm

if null ts then do if (null $ lookUp (parseMap pm0) i)

|| i == startIndex

then return ()

else addDiags [mkDiag FatalError

"no resolution for" a]

return Nothing

else if null $ tail ts then return (Just (getLastType pm, head ts))

else do addDiags [mkDiag Error

("ambiguous applications:\n\t" ++

(concatMap ( \ t -> showPretty t "\n\t" )

$ take 5 ts) ++ "for" ) a]

return Nothing

resolve :: GlobalAnnos -> (Type, Term) -> State Env (Maybe (Type, Term))

resolve ga (ty, trm) =

do pm <- resolveToParseMap ga ty trm

resolveFromParseMap (toAppl ga) (ty, trm) pm

resolveTerm :: GlobalAnnos -> Type -> Term -> State Env (Maybe Term)

resolveTerm ga ty trm =

do mr <- resolve ga (ty, trm)

return $ fmap snd mr

resolveAny :: GlobalAnnos -> Term -> State Env (Maybe (Type, Term))

resolveAny ga trm =

do tvar <- toEnvState freshVar

resolve ga (TypeName tvar star 1, trm)

-- ---------------------------------

-- patterns

-- ---------------------------------

extractBindings :: Pattern -> [VarDecl]

extractBindings pat =

case pat of

PatternVar l -> [l]

PatternConstr _ _ ps _ -> concatMap extractBindings ps

TuplePattern ps _ -> concatMap extractBindings ps

TypedPattern p _ _ -> extractBindings p

AsPattern p q _ -> extractBindings p ++ extractBindings q

_ -> error ("extractBindings: " ++ show pat)

patToToken :: Pattern -> Token

patToToken pat =

case pat of

PatternToken x -> x

TypedPattern _ _ _ -> inTok

_ -> error ("patToToken: " ++ show pat)

patFromState :: PState Pattern -> Pattern

patFromState p =

let r@(Id ts _ _)= ruleId p

sc@(TypeScheme _ (_ :=> _ty) _) = ruleScheme p

ar = reverse $ ruleArgs p

qs = reverse $ posList p

in if r == inId

|| r == opId

|| r == parenId

then head ar

else if r == applId then

case head ar of

PatternConstr instOp isc args ps ->

PatternConstr instOp isc (args ++ tail ar) (ps ++ qs)

t -> error ("patFromState: " ++ show t)

else if r == tupleId || r == unitId then

TuplePattern ar qs

else if isUnknownId r then

if null $ tail ts then error "patFromState"

else PatternVar (VarDecl (Id [head $ tail ts] [] [])

(ruleType p) Other qs)

else PatternConstr (InstOpId (setIdePos r ar qs) [] []) sc ar qs

initialPatState :: Assumps -> Index -> State Int [PState a]

initialPatState as i =

do let ids = concatMap (\ (ide, l) -> map ( \ e -> (ide, e)) $ opInfos l)

$ Map.toList as

l1 <- mapM (mkMixfixState i) ids

l2 <- mapM (mkPlainApplState i) $ filter (isMixfix . fst) ids

a <- mkApplTokState i applId

p <- mkParenTokState i parenId

t <- mkTupleTokState i tupleId

l3 <- mapM (mkTokState i)

[unitId,

unknownId,

inId,

opId]

return (a:p:t:l1 ++ l2 ++ l3)

nextPatState :: GlobalAnnos -> Knowns -> (Maybe Type, Pattern)

-> State (Env, ParseMap Pattern) ()

nextPatState ga knowns (ty, trm) =

do as <- gets (assumps . fst)

completeScanPredict ga knowns (ty, trm) patFromState patToToken

$ initialPatState as

iterPatStates :: GlobalAnnos -> Knowns -> Type -> [Pattern]

-> State (Env, ParseMap Pattern) ()

iterPatStates ga knowns ty pats =

do (e, pm) <- get

let self = iterPatStates ga knowns ty

if null pats then return ()

else case head pats of

MixfixPattern ts -> self (ts ++ tail pats)

BracketPattern b ts ps -> self

(expandPos PatternToken (getBrackets b) ts ps ++ tail pats)

TypedPattern hd typ ps ->

do let (mTyp, e1) = runState (anaStarType typ) e

(mtt, e2) = runState (case mTyp of

Nothing -> resolvePattern ga hd

Just nTyp -> resolvePat ga (nTyp, hd)) e1

put (e2, pm)

case mtt of

Just (_, ttt) ->

do case mTyp of

Nothing -> return ()

Just nTyp -> do

nextPatState ga knowns (mTyp,

TypedPattern ttt nTyp ps)

self (tail pats)

Nothing -> return ()

t@(PatternToken _) -> do nextPatState ga knowns (Nothing, t)

self (tail pats)

t -> error ("iterPatStates: " ++ show t)

getKnowns :: Id -> Knowns

getKnowns (Id ts cs _) = Set.union (Set.fromList (map tokStr ts)) $

Set.unions (map getKnowns cs)

resolvePatToParseMap :: GlobalAnnos -> Type -> Pattern

-> State Env (ParseMap Pattern)

resolvePatToParseMap ga ty trm =

do as <- gets assumps

initStates <- toEnvState $ initialPatState as startIndex

let ids = Map.keys as

knowns = Set.union (Set.fromList

(tokStr inTok : map (:[]) "{}[](),"))

$ Set.unions $ map getKnowns ids

e <- get

let (e2, pm2) = execState (iterPatStates ga knowns ty [trm])

(e, ParseMap

{ lastIndex = startIndex

, parseMap = Map.single startIndex initStates })

put e2

return pm2

resolvePattern :: GlobalAnnos -> Pattern -> State Env (Maybe (Type, Pattern))

resolvePattern ga trm =

do tvar <- toEnvState freshVar

resolvePat ga (TypeName tvar star 1, trm)

resolvePat :: GlobalAnnos -> (Type, Pattern)

-> State Env (Maybe (Type, Pattern))

resolvePat ga (ty, trm) =

do pm <- resolvePatToParseMap ga ty trm

mr <- resolveFromParseMap patFromState (ty, trm) pm

case mr of

Nothing -> return Nothing

Just (newTy, pat) ->

do e <- get

let (r, (c, _, ds)) =

runState (specializePatVars

(typeMap e) (newTy, pat))

(counter e, Map.empty, [])

put e { counter = c }

if null ds then return $ Just r

else do addDiags ds

return Nothing

-- ---------------------------------------------------------------------------

-- specialize

-- ---------------------------------------------------------------------------

getArgsRes :: Type -> [a] -> Result ([Type], Type)

getArgsRes t [] = return ([], t)

getArgsRes (FunType t1 _ t2 _) (_:r) =

do (as, res) <- getArgsRes t2 r

return (t1:as, res)

getArgsRes t _ = Result [mkDiag FatalError "too many arguments for type" t]

Nothing

specializePatVars :: TypeMap -> (Type, Pattern)

-> State (Int, Subst, [Diagnosis]) (Type, Pattern)

specializePatVars tm (ty, pat) = do

(c, oldSubst, ds) <- get

case pat of

PatternVar (VarDecl v vty k ps) ->

do let r = unify tm (subst oldSubst ty) $ subst oldSubst vty

case maybeResult r of

Nothing -> do put (c, oldSubst, diags r ++ ds)

return (ty, pat)

Just newSubst ->

do put (c, newSubst, ds)

return (subst newSubst ty,

PatternVar $ VarDecl v

(subst newSubst vty) k ps)

PatternConstr i sc args ps ->

do let (ity, c2) = runState (freshInst sc) c

argsRes = getArgsRes ity args

case maybeResult argsRes of

Nothing -> do put (c2, oldSubst, diags argsRes ++ ds)

return (ty, pat)

Just (ats, res) ->

do let r = unify tm (subst oldSubst ty)

$ subst oldSubst res

case maybeResult r of

Nothing -> do put (c2, oldSubst, diags r ++ ds)

return (ty, pat)

Just newSubst ->

do put (c2, newSubst, ds)

largs <- mapM (specializePatVars tm)

$ zip ats args

(_, lastSubst, _) <- get

return (subst lastSubst res,

PatternConstr i sc (map snd largs) ps)

TuplePattern args ps ->

case ty of

ProductType ats qs ->

if length ats == length args then

do largs <- mapM (specializePatVars tm) $ zip ats args

(_, lastSubst,_) <- get

return (subst lastSubst $ ProductType (map fst largs) qs

, TuplePattern (map snd largs) ps)

else do put (c, oldSubst, mkDiag Error

"wrong number of arguments for tuple" ty : ds)

return (ty, pat)

_ -> do put (c, oldSubst, mkDiag Error

"wrong type for tuple" pat : ds)

return (ty, pat)

TypedPattern tpat vty ps ->

do let r = unify tm (subst oldSubst ty)

$ subst oldSubst vty

case maybeResult r of

Nothing -> do put (c, oldSubst, diags r ++ ds)

return (ty, pat)

Just newSubst ->

do put (c, newSubst, ds)

(newTy, newPat) <- specializePatVars tm

(subst newSubst vty, tpat)

return (newTy, case newPat of

PatternVar _ -> newPat

TypedPattern _ _ _ -> newPat

PatternConstr _ (TypeScheme [] _ _) [] _ ->

newPat

_ -> TypedPattern newPat newTy ps)

_ -> error ("specializePatVars: " ++ show pat)