{- |

Module : $Header$

Copyright : (c) Christian Maeder and Uni Bremen 2003

Licence : similar to LGPL, see HetCATS/LICENCE.txt or LIZENZ.txt

Maintainer : hets@tzi.de

Stability : experimental

Portability : portable

analyse operation declarations

-}

module HasCASL.OpDecl where

import HasCASL.As

import HasCASL.VarDecl

import HasCASL.Le

import Common.Lib.State

import Common.Result

import Common.GlobalAnnotations

import HasCASL.Unify

import HasCASL.TypeAna

import HasCASL.TypeCheck

import HasCASL.MixAna

import Data.Maybe

import Data.List

anaAttr :: GlobalAnnos -> TypeScheme -> OpAttr -> State Env (Maybe OpAttr)

anaAttr ga (TypeScheme tvs (_ :=> ty) _) (UnitOpAttr trm ps) =

do let mTy = case ty of

FunType (ProductType [t1, t2] _) _ t3 _ ->

Just (t1,t2,t3)

FunType t1 _ (FunType t2 _ t3 _) _ ->

Just (t1,t2,t3)

_ -> Nothing

tm <- gets typeMap

mapM_ (addTypeVarDecl False) tvs

case mTy of

Nothing -> do addDiags [mkDiag Error

"unexpected type of operation" ty]

mt <- resolveTerm ga Nothing trm

putTypeMap tm

case mt of

Nothing -> return Nothing

Just t -> return $ Just $ UnitOpAttr t ps

Just (t1, t2, t3) ->

do if t1 == t2 && t2 == t3 then

return ()

else addDiags [mkDiag Error

"unexpected type of operation" ty]

mt <- resolveTerm ga (Just t3) trm

putTypeMap tm

case mt of Nothing -> return Nothing

Just t -> return $ Just $ UnitOpAttr t ps

anaAttr _ _ b = return $ Just b

filterVars :: Assumps -> Assumps

filterVars = filterAssumps (not . isVarDefn)

patternsToType :: [Pattern] -> Type -> Type

patternsToType [] t = t

patternsToType (p: ps) t = FunType (tuplePatternToType p) PFunArr

(patternsToType ps t) []

tuplePatternToType :: Pattern -> Type

tuplePatternToType (PatternVar (VarDecl _ t _ _)) = t

tuplePatternToType (TuplePattern ps qs) =

ProductType (map tuplePatternToType ps) qs

tuplePatternToType _ = error "tuplePatternToType"

anaOpItem :: GlobalAnnos -> OpBrand -> OpItem -> State Env OpItem

anaOpItem ga br (OpDecl is sc attr ps) =

do mSc <- anaTypeScheme sc

let nSc = case mSc of

Nothing -> sc

Just s -> generalize s

mAttrs <- mapM (anaAttr ga nSc) attr

us <- mapM (anaOpId br nSc attr) is

return $ OpDecl (catMaybes us) nSc (catMaybes mAttrs) ps

anaOpItem ga br (OpDefn o oldPats sc partial trm ps) =

do let (op@(OpId i _ _), extSc) = getUninstOpId sc o

l <- mapM extractBindings oldPats

let bs = concatMap snd l

pats = map fst l

mSc <- anaTypeScheme extSc

as <- gets assumps

checkUniqueVars bs

putAssumps $ filterVars as

mapM_ anaVarDecl bs

case mSc of

Just newSc@(TypeScheme tArgs (qu :=> _) qs) -> do

ty <- toEnvState $ freshInst newSc

mt <- resolveTerm ga (Just ty) trm

putAssumps as

case mt of

Nothing -> return $ OpDefn op pats

newSc partial trm ps

Just lastTrm -> do

let lastSc = TypeScheme tArgs

(qu :=> patternsToType pats ty) qs

addOpId i lastSc [] $ Definition br

$ case (pats, partial) of

([], Total) -> lastTrm

_ -> LambdaTerm pats partial

lastTrm ps

return $ OpDefn op [] lastSc

partial lastTrm ps

Nothing -> do

mt <- resolveTerm ga Nothing trm

putAssumps as

return $ OpDefn op pats extSc partial

(case mt of Nothing -> trm

Just x -> x) ps

getUninstOpId :: TypeScheme -> OpId -> (OpId, TypeScheme)

getUninstOpId (TypeScheme tvs q ps) (OpId i args qs) =

(OpId i [] qs, TypeScheme (args ++ tvs) q ps)

anaOpId :: OpBrand -> TypeScheme -> [OpAttr] -> OpId -> State Env (Maybe OpId)

anaOpId br sc attrs o =

do let (OpId i _ _, newSc) = getUninstOpId sc o

mo <- addOpId i newSc attrs $ NoOpDefn br

return $ fmap (const o) mo

anaTypeScheme :: TypeScheme -> State Env (Maybe TypeScheme)

anaTypeScheme (TypeScheme tArgs (q :=> ty) p) =

do tm <- gets typeMap -- save global variables

mArgs <- mapM anaTypeVarDecl tArgs

let newArgs = catMaybes mArgs

checkUniqueTypevars newArgs

mt <- anaStarType ty

putTypeMap tm -- forget local variables

case mt of

Nothing -> return Nothing

Just newTy -> return $ Just $ TypeScheme newArgs (q :=> newTy) p

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

-- ProgEq

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

anaProgEq :: GlobalAnnos -> ProgEq -> State Env ProgEq

anaProgEq ga pe@(ProgEq pat trm qs) =

do as <- gets assumps

putAssumps $ filterVars as

mp <- checkPattern ga pat

case mp of

Nothing -> return pe

Just np -> do

(newPat, exbs) <- extractBindings np

checkUniqueVars exbs

mapM_ addVarDecl exbs

mt <- resolveTerm ga Nothing trm

putAssumps as

case mt of

Just newTerm ->

let (topPat, args) = getApplConstr newPat

defTrm = if null args then newTerm

else LambdaTerm (reverse args)

Partial newTerm []

in case topPat of

PatternConstr (InstOpId i _tys _) sc _ -> do

addOpId i sc [] $ Definition Op defTrm

return $ ProgEq newPat newTerm qs

_ -> do addDiags $ [mkDiag Error

"illegal toplevel pattern"

topPat]

return pe

_ -> return $ ProgEq newPat trm qs

getApplConstr :: Pattern -> (Pattern, [Pattern])

getApplConstr pat =

case pat of

ApplPattern p1 p2 _ ->

let (tp, args) = getApplConstr p1 in (tp, p2:args)

TypedPattern tp _ _ -> getApplConstr tp

_ -> (pat, [])