implementation module sem import qualified Data.Map as Map from Data.Func import $ import Data.Maybe import Data.Void import Data.Either import Data.Functor import Control.Applicative import Control.Monad import Control.Monad.State import Control.Monad.Identity import Math.Random import Control.Monad.Trans import StdMisc from StdFunc import id, const, o import StdString import StdTuple import StdList import StdBool import GenEq from Text import class Text(concat), instance Text String import AST :: Gamma :== ('Map'.Map String Type, [String]) :: Env a :== StateT Gamma (Either SemError) a //StateT (Gamma -> Either SemError (a, Gamma)) //we need to redefine this even though it is in Control.Monad.State instance MonadTrans (StateT Gamma) where liftT m = StateT \s-> m >>= \a-> return (a, s) get :== gets id sem :: AST -> SemOutput sem (AST vd fd) = case runStateT m ('Map'.newMap, getRandomStream 1) of Left e = Left [e] Right ((vds, fds), gamma) = Right ((AST vds fds), gamma) where m :: Env ([VarDecl], [FunDecl]) m = mapM semVarDecl vd >>= \vd1 -> mapM semFunDecl fd >>= \fd1 -> mapM semVarDecl vd1 >>= \vd2 -> mapM semFunDecl fd1 >>= \fd2 -> mapM semVarDecl vd2 >>= \vd3 -> mapM semFunDecl fd2 >>= \fd3 -> mapM semVarDecl vd3 >>= \vd4 -> mapM semFunDecl fd3 >>= \fd4 -> //Dit is puur om te proberen pure (vd4, fd4) semFunDecl :: FunDecl -> Env FunDecl semFunDecl fd=:(FunDecl p f args mt vds stmts) = (case mt of Nothing = genType args >>= \infft->putIdent f infft >>| pure infft Just t = putIdent f t >>| pure t) >>= \ft -> saveGamma >>= \gamma -> matchFunctions args ft >>= \tres-> mapM semVarDecl vds >>= \newvds-> mapM (checkStmt tres) stmts >>= \newstmts-> inferReturnType stmts >>= \returntype-> case mt of Nothing = reconstructType args tres >>= \ftype->restoreGamma gamma >>| putIdent f ftype >>| pure ( FunDecl p f args (Just ftype) newvds newstmts) Just t = restoreGamma gamma >>| updateFunType t returntype >>= \tt-> pure (FunDecl p f args (Just tt) newvds newstmts) updateFunType :: Type Type -> Env Type updateFunType t1 t2 = unify t1 t2 updateFunType (t1 ->> t2) t3 = t1 ->> (updateFunType t2 t3) inferReturnType :: [Stmt] -> Env Type inferReturnType [] = pure VoidType inferReturnType [ReturnStmt (Just t):rest] = typeExpr t >>= \tx->inferReturnType rest >>= \ty->unify tx ty inferReturnType [ReturnStmt _:rest] = inferReturnType rest >>= \tx-> unify VoidType tx inferReturnType [_:rest] = inferReturnType rest reconstructType :: [String] Type -> Env Type reconstructType [] t = pure t reconstructType [x:xs] t = gets (\(st, r)->'Map'.get x st) >>= \mtype->case mtype of Nothing = liftT $ Left $ Error "Not used ????" Just type = reconstructType xs t >>= \resttype->pure (type ->> resttype) genType :: [String] -> Env Type genType [] = freshIdent >>= \fi->pure $ IdType fi genType [x:xs] = liftM2 (->>) (freshIdent >>= \fi->pure $ IdType fi) (genType xs) matchFunctions :: [String] Type -> Env Type matchFunctions [] (_ ->> _) = liftT $ Left $ ArgumentMisMatchError zero "Not enough arguments" matchFunctions _ (VoidType ->> _) = liftT $ Left $ ArgumentMisMatchError zero "Void can't be a non return type" matchFunctions [x:xs] (t1 ->> t2) = modify (\(st, r)->('Map'.put x t1 st, r)) >>| matchFunctions xs t2 matchFunctions [] t = pure t matchFunctions _ t = liftT $ Left $ ArgumentMisMatchError zero "Too much argumnts" semVarDecl :: VarDecl -> Env VarDecl semVarDecl (VarDecl pos type ident ex) = unify type ex >>= \t-> putIdent ident t >>| (pure $ VarDecl pos t ident ex) checkStmt ::Type Stmt -> Env Stmt checkStmt t (IfStmt c st se) = unify BoolType c >>| mapM (checkStmt t) st >>= \st1-> mapM (checkStmt t) se >>= \se1-> pure (IfStmt c st1 se1) checkStmt t w=:(WhileStmt c et) = unify BoolType c >>| mapM (checkStmt t) et >>= \et1-> pure w checkStmt t a=:(AssStmt (VarDef ident fs) e) = gets (\(st, r)->'Map'.get ident st) >>= \mt->case mt of Nothing = liftT $ Left $ UndeclaredVariableError zero ident Just t = unify t fs >>= \t1 -> unify t1 e >>| pure a checkStmt t r=:(FunStmt (FunCall f es)) = typeFun f es >>| pure r checkStmt VoidType r=:(ReturnStmt Nothing) = pure r checkStmt t r=:(ReturnStmt (Just e)) = unify t e >>| pure r typeExpr :: Expr -> Env Type typeExpr (IntExpr _ _) = pure IntType typeExpr (CharExpr _ _) = pure CharType typeExpr (BoolExpr _ _) = pure BoolType typeExpr (Op1Expr p UnNegation expr) = unify BoolType expr typeExpr (Op1Expr p UnMinus expr) = unify IntType expr typeExpr (TupleExpr p (e1, e2)) = typeExpr e1 >>= \t1-> typeExpr e2 >>= \t2-> pure $ TupleType (t1, t2) typeExpr (Op2Expr p e1 op e2) | isMember op [BiPlus, BiMinus, BiTimes, BiDivide, BiMod] = typeOp2 e1 e2 op [IntType] IntType | isMember op [BiEquals, BiUnEqual] = typeOp2 e1 e2 op [IntType, BoolType, CharType] BoolType | isMember op [BiLesser, BiGreater, BiLesserEq, BiGreaterEq] = typeOp2 e1 e2 op [IntType, CharType] BoolType | isMember op [BiAnd, BiOr] = typeOp2 e1 e2 op [BoolType] BoolType | op == BiCons = typeExpr e1 >>= \t1-> typeExpr e2 >>= \t2-> unify (ListType t1) t2 typeExpr (EmptyListExpr p) = freshIdent >>= \frsh-> let t = IdType frsh in putIdent frsh t >>| pure t typeExpr (FunExpr p (FunCall f es)) = typeFun f es typeExpr (VarExpr p (VarDef ident fs)) = gets (\(st, r)->'Map'.get ident st) >>= \mt->case mt of Nothing = liftT $ Left $ UndeclaredVariableError p ident Just t = unify t fs typeOp2 :: Expr Expr Op2 [Type] Type -> Env Type typeOp2 e1 e2 op ts ret = typeExpr e1 >>= \t1-> typeExpr e2 >>= \t2-> unify t1 t2 >>= \t3->if (isMember t3 [IdType "":ts]) (pure ret) (liftT $ Left $ OperatorError (extrPos e1) op t3) buildFunctionType :: String [Expr] -> Env Type buildFunctionType frsh [] = let t = IdType frsh in putIdent frsh t >>| pure t buildFunctionType frsh [e:es] = (->>) <$> typeExpr e <*> buildFunctionType frsh es unifyApp :: Type [Expr] -> Env Type unifyApp t [] = pure t unifyApp (tf1 ->> tf2) [t1:ts] = unify tf1 t1 >>| unifyApp tf2 ts unifyApp t1 t2 = liftT $ Left $ UnifyError zero t1 (IdType "[expressions, FIXME]") typeFun :: String [Expr] -> Env Type typeFun f es = gets (\(st, r)->'Map'.get f st) >>= \mt-> case mt of Nothing = freshIdent >>= \frsh-> buildFunctionType frsh es >>= \ft-> putIdent f ft >>| (pure $ IdType frsh) Just t = unifyApp t es resultType :: Type -> Type resultType (_ ->> t) = resultType t resultType t = t class unify a :: Type a -> Env Type instance unify [FieldSelector] where unify t [] = pure t unify (ListType t) [FieldHd:fs] = unify t fs unify t=:(ListType _) [FieldTl:fs] = unify t fs unify (TupleType (t, _)) [FieldFst:fs] = unify t fs unify (TupleType (_, t)) [FieldSnd:fs] = unify t fs unify t [fs:_] = liftT $ Left $ FieldSelectorError zero t fs instance unify Expr where unify (_ ->> _) e = liftT $ Left $ ParseError (extrPos e) "Expression cannot be a higher order function. Yet..." unify VoidType e = liftT $ Left $ ParseError (extrPos e) "Expression cannot be a Void type." // unify (IdType _) e = liftT $ Left $ ParseError (extrPos e) // "Expression cannot be an polymorf type." unify VarType e = typeExpr e //we have to cheat to decorate the error, can be done nicer? unify t=:(IdType id) e = typeExpr e >>= \tex->unify t tex >>= \type->putIdent id type >>| pure type unify t e = StateT $ \s0 -> let res = runStateT m s0 in case res of Left err = Left $ decErr e err Right t = Right t //note, t :: (Type, Gamma) where m = typeExpr e >>= \tex-> unify t tex instance unify Type where unify IntType IntType = pure IntType unify BoolType BoolType = pure BoolType unify CharType CharType = pure CharType unify (IdType i) t=:(IdType j) = replace i t >>| pure t unify t (IdType i) = unify (IdType i) t unify (IdType i) t = replace i t >>| pure t unify (ListType t1) (ListType t2) = unify t1 t2 >>| (pure $ ListType t1) unify (ta1 ->> ta2) (tb1 ->> tb2) = unify ta1 tb1 >>= \ta-> unify ta2 tb2 >>= \tb-> pure (ta ->> tb) unify VoidType t = pure t unify t VoidType = pure t unify VoidType VoidType = pure VoidType unify t1 t2 = liftT $ Left $ UnifyError zero t1 t2 instance zero Pos where zero = {line=0,col=0} decErr :: Expr SemError -> SemError decErr e (UnifyError _ t1 t2) = UnifyError (extrPos e) t1 t2 decErr e (FieldSelectorError _ t fs) = FieldSelectorError (extrPos e) t fs decErr e (ParseError _ s) = ParseError (extrPos e) s decErr e err = err dc2 :: Expr (Either SemError a) -> Either SemError a dc2 e (Right t) = Right t dc2 e (Left err) = Left err extrPos :: Expr -> Pos extrPos (VarExpr p _) = p extrPos (Op2Expr p _ _ _) = p extrPos (Op1Expr p _ _) = p extrPos (IntExpr p _) = p extrPos (CharExpr p _) = p extrPos (BoolExpr p _) = p extrPos (FunExpr p _) = p extrPos (EmptyListExpr p) = p extrPos (TupleExpr p _) = p instance toString Gamma where toString (mp, _) = concat [concat [k, ": ", toString v, "\n"]\\(k, v) <- 'Map'.toList mp] getRandomStream :: Int -> [String] getRandomStream i = genIdents $ filter (isAlpha o toChar) (genRandInt i) where genIdents r = let (ic, r2) = splitAt 5 r in [toString ic: genIdents r2] freshIdent :: Env String freshIdent = get >>= \(st, [ident:rest])-> put (st, rest) >>| case 'Map'.get ident st of Nothing = pure ident _ = freshIdent putIdent :: String Type -> Env Void putIdent i t = gets (\(st, r)->'Map'.get i st) >>= \mt -> case mt of Nothing = modify (\(st, r)->('Map'.put i t st, r)) Just t2 = unify t t2 >>= \t3-> modify (\(st, r)->('Map'.put i t3 st, r)) replace :: String Type -> Env Void replace ident type = get >>= \(st, fr)->put ('Map'.fromList $ map (itupdate ident type) ('Map'.toList st), fr) where itupdate :: String Type (String, Type) -> (String, Type) itupdate ident newtype ov=:(key, IdType type) = if (ident == type) (key, newtype) ov itupdate ident newtype (key, TupleType (t1, t2)) # (_, t1) = itupdate ident newtype (key, t1) # (_, t2) = itupdate ident newtype (key, t2) = (key, TupleType (t1, t2)) itupdate ident newtype (key, ListType t1) # (_, t1) = itupdate ident newtype (key, t1) = (key, ListType t1) itupdate _ _ k = k instance toString SemError where toString (ParseError p e) = concat [toString p, "SemError: ParseError: ", e] toString (UnifyError p t1 t2) = concat [ toString p, "SemError: Cannot unify types. Expected: ", toString t1, ". Given: ", toString t2] toString (FieldSelectorError p t fs) = concat [ toString p, "SemError: Cannot select ", toString fs, " from type: ", toString t] toString (OperatorError p o t) = concat [ toString p, "SemError: No ", toString o, " for type ", toString t] toString (UndeclaredVariableError p ident) = concat [ toString p, "SemError: identifier: ", ident, " undefined."] toString (ArgumentMisMatchError p s) = concat [toString p, "SemError: Argument mismatch: ", s] toString (Error e) = "SemError: " +++ e saveGamma :: Env Gamma saveGamma = get restoreGamma :: Gamma -> Env Void restoreGamma (oldstate, _) = gets snd >>= \newr->put (oldstate, newr) derive gEq Type instance == Type where (==) (IdType _) (IdType _) = True (==) o1 o2 = gEq{|*|} o1 o2