{- |

Module : $Header$

Description : mixfix analysis for terms

Copyright : (c) Christian Maeder and Uni Bremen 2003-2005

License : similar to LGPL, see HetCATS/LICENSE.txt or LIZENZ.txt

Maintainer : Christian.Maeder@dfki.de

Stability : experimental

Portability : portable

Mixfix analysis of terms and patterns, type annotations are also analysed

-}

module HasCASL.MixAna

( resolve

, anaPolyId

, makeRules

, getPolyIds

, iterateCharts

, toMixTerm

) where

import Common.GlobalAnnotations

import Common.Result

import Common.Id

import Common.DocUtils

import Common.Earley

import Common.Lexer

import Common.Prec

import Common.ConvertMixfixToken

import Common.Lib.State

import Common.AnnoState

import Common.Anno_Parser

import qualified Data.Map as Map

import qualified Data.Set as Set

import HasCASL.As

import HasCASL.AsUtils

import HasCASL.PrintAs

import HasCASL.Unify

import HasCASL.VarDecl

import HasCASL.Le

import HasCASL.ParseTerm

import HasCASL.TypeAna

import qualified Text.ParserCombinators.Parsec as P

import Data.Maybe

import Control.Exception (assert)

addType :: Term -> Term -> Term

addType (MixTypeTerm q ty ps) t = TypedTerm t q ty ps

addType _ _ = error "addType"

-- | try to reparse terms as a compound list

isCompoundList :: Set.Set [Id] -> [Term] -> Bool

isCompoundList compIds =

maybe False (flip Set.member compIds) . mapM reparseAsId

isTypeList :: Env -> [Term] -> Bool

isTypeList e l = case mapM termToType l of

Nothing -> False

Just ts ->

let Result ds ml = mapM ( \ t -> anaTypeM (Nothing, t) e) ts

in isJust ml && not (hasErrors ds)

termToType :: Term -> Maybe Type

termToType t = case P.runParser ((case getPosList t of

[] -> return ()

p : _ -> P.setPosition $ fromPos p)

>> parseType << P.eof) (emptyAnnos ()) "" $ showDoc t "" of

Right x -> Just x

_ -> Nothing

anaPolyId :: PolyId -> TypeScheme -> State Env (Maybe TypeScheme)

anaPolyId (PolyId i@(Id _ cs _) _ _) sc = do

mSc <- anaTypeScheme sc

case mSc of

Nothing -> return Nothing

Just newSc@(TypeScheme tvars _ _) -> do

e <- get

let ids = Set.unions

[ Map.keysSet $ classMap e

, Map.keysSet $ typeMap e

, Map.keysSet $ assumps e ]

es = filter (not . flip Set.member ids) cs

addDiags $ map (\ j -> mkDiag Warning

"unexpected identifier in compound list" j) es

if null cs || null tvars then return () else

addDiags [mkDiag Hint "is polymorphic compound identifier" i]

return $ Just newSc

resolveQualOp :: PolyId -> TypeScheme -> State Env TypeScheme

resolveQualOp i@(PolyId j _ _) sc = do

mSc <- anaPolyId i sc

e <- get

case mSc of

Nothing -> return sc -- and previous

Just nSc -> do

if Set.null $ Set.filter ((== nSc) . opType)

$ Map.findWithDefault Set.empty j $ assumps e

then addDiags [mkDiag Error "operation not found" j]

else return ()

return nSc

iterateCharts :: GlobalAnnos -> Set.Set [Id] -> [Term] -> Chart Term

-> State Env (Chart Term)

iterateCharts ga compIds terms chart = do

e <- get

let self = iterateCharts ga compIds

oneStep = nextChart addType (toMixTerm e) ga chart

vs = localVars e

tm = typeMap e

case terms of

[] -> return chart

t : tt -> let recurse trm = self tt $ oneStep

(trm, exprTok {tokPos = getRange trm}) in case t of

MixfixTerm ts -> self (ts ++ tt) chart

MixTypeTerm q typ ps -> do

mTyp <- anaStarType typ

case mTyp of

Nothing -> recurse t

Just nTyp -> self tt $ oneStep

(MixTypeTerm q (monoType nTyp) ps, typeTok {tokPos = ps})

BracketTerm b ts ps ->

let bres = self (expandPos TermToken

(getBrackets b) ts ps ++ tt) chart in case (b, ts) of

(Squares, _ : _) -> if isCompoundList compIds ts then do

addDiags [mkDiag Hint "is compound list" t]

bres

else if isTypeList e ts then do

let testChart = oneStep (t, typeInstTok {tokPos = ps})

if null $ solveDiags testChart then do

addDiags [mkDiag Hint "is type list" t]

self tt testChart

else bres

else bres

_ -> case (b, ts, tt) of

(Parens, [QualOp b2 v sc [] _ ps2], hd@(BracketTerm Squares

ts2@(_ : _) ps3) : rtt) | isTypeList e ts2 -> do

addDiags [mkDiag Hint "is type list" ts2]

nSc <- resolveQualOp v sc

self rtt $ oneStep

( QualOp b2 v nSc (bracketTermToTypes e hd) UserGiven ps2

, exprTok {tokPos = appRange ps ps3})

_ -> bres

QualVar (VarDecl v typ ok ps) -> do

mTyp <- anaStarType typ

recurse $ maybe t ( \ nType -> QualVar $ VarDecl v (monoType nType)

ok ps) mTyp

QualOp b v sc [] k ps -> do

nSc <- resolveQualOp v sc

recurse $ QualOp b v nSc [] k ps

QuantifiedTerm quant decls hd ps -> do

newDs <- mapM (anaddGenVarDecl False) decls

mt <- resolve ga hd

putLocalVars vs

putTypeMap tm

recurse $ QuantifiedTerm quant (catMaybes newDs) (maybe hd id mt) ps

LambdaTerm decls part hd ps -> do

mDecls <- mapM (resolvePattern ga) decls

let anaDecls = catMaybes mDecls

bs = concatMap extractVars anaDecls

checkUniqueVars bs

mapM_ (addLocalVar False) bs

mt <- resolve ga hd

putLocalVars vs

recurse $ LambdaTerm anaDecls part (maybe hd id mt) ps

CaseTerm hd eqs ps -> do

mt <- resolve ga hd

newEs <- resolveCaseEqs ga eqs

recurse $ CaseTerm (maybe hd id mt) newEs ps

LetTerm b eqs hd ps -> do

newEs <- resolveLetEqs ga eqs

mt <- resolve ga hd

putLocalVars vs

recurse $ LetTerm b newEs (maybe hd id mt) ps

TermToken tok -> do

let (ds1, trm) = convertMixfixToken (literal_annos ga)

(flip ResolvedMixTerm []) TermToken tok

addDiags ds1

self tt $ oneStep $ case trm of

TermToken _ -> (trm, tok)

_ -> (trm, exprTok {tokPos = tokPos tok})

AsPattern vd p ps -> do

mp <- resolvePattern ga p

recurse $ AsPattern vd (maybe p id mp) ps

TypedTerm trm k ty ps -> do

-- assume that type is analysed

mt <- resolve ga trm

recurse $ TypedTerm (maybe trm id mt) k ty ps

_ -> error ("iterCharts: " ++ show t)

-- * equation stuff

resolveCaseEq :: GlobalAnnos -> ProgEq -> State Env (Maybe ProgEq)

resolveCaseEq ga (ProgEq p t ps) = do

mp <- resolvePattern ga p

case mp of

Nothing -> return Nothing

Just newP -> do

let bs = extractVars newP

checkUniqueVars bs

vs <- gets localVars

mapM_ (addLocalVar False) bs

mtt <- resolve ga t

putLocalVars vs

return $ case mtt of

Nothing -> Nothing

Just newT -> Just $ ProgEq newP newT ps

resolveCaseEqs :: GlobalAnnos -> [ProgEq] -> State Env [ProgEq]

resolveCaseEqs ga eqs = case eqs of

[] -> return []

eq : rt -> do

mEq <- resolveCaseEq ga eq

reqs <- resolveCaseEqs ga rt

return $ case mEq of

Nothing -> reqs

Just newEq -> newEq : reqs

resolveLetEqs :: GlobalAnnos -> [ProgEq] -> State Env [ProgEq]

resolveLetEqs _ [] = return []

resolveLetEqs ga eqs = case eqs of

[] -> return []

ProgEq pat trm ps : rt -> do

mPat <- resolvePattern ga pat

case mPat of

Nothing -> do

resolve ga trm

resolveLetEqs ga rt

Just newPat -> do

let bs = extractVars newPat

checkUniqueVars bs

mapM_ (addLocalVar False) bs

mTrm <- resolve ga trm

case mTrm of

Nothing -> resolveLetEqs ga rt

Just newTrm -> do

reqs <- resolveLetEqs ga rt

return $ ProgEq newPat newTrm ps : reqs

mkPatAppl :: Term -> Term -> Range -> Term

mkPatAppl op arg qs = case op of

QualVar (VarDecl i (MixfixType []) _ _) -> ResolvedMixTerm i [] [arg] qs

_ -> ApplTerm op arg qs

bracketTermToTypes :: Env -> Term -> [Type]

bracketTermToTypes e t = case t of

BracketTerm Squares tys _ ->

map (monoType . snd) $ maybe (error "bracketTermToTypes") id $

maybeResult $ mapM ( \ ty -> anaTypeM (Nothing, ty) e) $

maybe (error "bracketTermToTypes1") id $ mapM termToType tys

_ -> error "bracketTermToTypes2"

toMixTerm :: Env -> Id -> [Term] -> Range -> Term

toMixTerm e i ar qs =

if i == applId then assert (length ar == 2) $

let [op, arg] = ar in mkPatAppl op arg qs

else if i == tupleId || i == unitId then

mkTupleTerm ar qs

else case unPolyId i of

Just j@(Id ts _ _) -> if isMixfix j && isSingle ar then

ResolvedMixTerm j (bracketTermToTypes e $ head ar) [] qs

else assert (length ar == 1 + placeCount j) $

let (far, tar : sar) =

splitAt (placeCount $ mkId $ fst $ splitMixToken ts) ar

in ResolvedMixTerm j (bracketTermToTypes e tar) (far ++ sar) qs

_ -> ResolvedMixTerm i [] ar qs

getKnowns :: Id -> Set.Set Token

getKnowns (Id ts cs _) =

Set.union (Set.fromList ts) $ Set.unions $ map getKnowns cs

resolvePattern :: GlobalAnnos -> Term -> State Env (Maybe Term)

resolvePattern = resolver True

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

resolve = resolver False

resolver :: Bool -> GlobalAnnos -> Term -> State Env (Maybe Term)

resolver isPat ga trm = do

e <- get

let ass = assumps e

vs = localVars e

ps = preIds e

compIds = getCompoundLists e

(addRule, ruleS, sIds) = makeRules ga ps (getPolyIds ass)

$ Set.union (Map.keysSet ass) $ Map.keysSet vs

chart <- iterateCharts ga compIds [trm] $ initChart addRule ruleS

let Result ds mr = getResolved (showDoc . parenTerm) (getRange trm)

(toMixTerm e) chart

addDiags ds

if isPat then case mr of

Nothing -> return mr

Just pat -> fmap Just $ anaPattern sIds pat

else return mr

getPolyIds :: Assumps -> Set.Set Id

getPolyIds = Set.unions . map ( \ (i, s) ->

Set.fold ( \ oi -> case opType oi of

TypeScheme (_ : _) _ _ -> Set.insert i

_ -> id) Set.empty s) . Map.toList

uTok :: Token

uTok = mkSimpleId "_"

builtinIds :: [Id]

builtinIds = [unitId, parenId, tupleId, exprId, typeId, applId]

makeRules :: GlobalAnnos -> (PrecMap, Set.Set Id) -> Set.Set Id

-> Set.Set Id -> (Token -> [Rule], Rules, Set.Set Id)

makeRules ga ps@(p, _) polyIds aIds =

let (sIds, ids) = Set.partition isSimpleId aIds

ks = Set.fold (Set.union . getKnowns) Set.empty ids

rIds = Set.union ids $ Set.intersection sIds $ Set.map simpleIdToId ks

m2 = maxWeight p + 2

in ( \ tok -> if isSimpleToken tok

&& not (Set.member tok ks)

|| tok == uTok then

[(simpleIdToId tok, m2, [tok])] else []

, partitionRules $ listRules m2 ga ++

initRules ps (Set.toList polyIds) builtinIds (Set.toList rIds)

, sIds)

initRules :: (PrecMap, Set.Set Id) -> [Id] -> [Id] -> [Id] -> [Rule]

initRules (p, ps) polyIds bs is =

map ( \ i -> mixRule (getIdPrec p ps i) i)

(bs ++ is) ++

map ( \ i -> (protect i, maxWeight p + 3, getPlainTokenList i))

(filter isMixfix is) ++

-- identifiers with a positive number of type arguments

map ( \ i -> ( polyId i, getIdPrec p ps i

, getPolyTokenList i)) polyIds ++

map ( \ i -> ( protect $ polyId i, maxWeight p + 3

, getPlainPolyTokenList i)) (filter isMixfix polyIds)

-- create fresh type vars for unknown ids tagged with type MixfixType [].

anaPattern :: Set.Set Id -> Term -> State Env Term

anaPattern s pat = case pat of

QualVar vd -> do

newVd <- checkVarDecl vd

return $ QualVar newVd

ResolvedMixTerm i tys pats ps | null pats && null tys &&

(isSimpleId i || i == simpleIdToId uTok) &&

not (Set.member i s) -> do

(tvar, c) <- toEnvState $ freshVar i

return $ QualVar $ VarDecl i (TypeName tvar rStar c) Other ps

| otherwise -> do

l <- mapM (anaPattern s) pats

return $ ResolvedMixTerm i tys l ps

ApplTerm p1 p2 ps -> do

p3 <- anaPattern s p1

p4 <- anaPattern s p2

return $ ApplTerm p3 p4 ps

TupleTerm pats ps -> do

l <- mapM (anaPattern s) pats

return $ TupleTerm l ps

TypedTerm p q ty ps -> do

case p of

QualVar (VarDecl v (MixfixType []) ok qs) ->

return $ QualVar $ VarDecl v ty ok $ appRange qs ps

_ -> do

newP <- anaPattern s p

return $ TypedTerm newP q ty ps

AsPattern vd p2 ps -> do

newVd <- checkVarDecl vd

p4 <- anaPattern s p2

return $ AsPattern newVd p4 ps

_ -> return pat

where checkVarDecl vd@(VarDecl v t ok ps) = case t of

MixfixType [] -> do

(tvar, c) <- toEnvState $ freshVar v

return $ VarDecl v (TypeName tvar rStar c) ok ps

_ -> return vd