From c9a2ff29fb4482fc1f43cf0386198a7d0e4a5f9b Mon Sep 17 00:00:00 2001 From: pimjager Date: Tue, 12 Apr 2016 23:24:49 +0200 Subject: [PATCH] Working Monad transformer except for Clean not finding an existing instance --- sem.icl | 96 +++++++++++++++++++++++---------------------------------- 1 file changed, 38 insertions(+), 58 deletions(-) diff --git a/sem.icl b/sem.icl index 6c78854..a973a02 100644 --- a/sem.icl +++ b/sem.icl @@ -9,6 +9,7 @@ import Control.Applicative import Control.Monad import Control.Monad.State import Control.Monad.Identity +import Control.Monad.Trans import StdMisc from StdFunc import id, const import StdString @@ -20,27 +21,9 @@ import AST from parse import :: ParserOutput, :: Error :: Gamma :== 'Map'.Map String Type -:: Env a = Env (State Gamma (Either SemError a)) +:: Env a :== StateT Gamma (Either SemError) a -instance Functor Env where - fmap f m = liftM f m - -instance Applicative Env where - (<*>) f g = ap f g - pure a = Env $ pure $ Right a - -//instance Alternative Env where -// empty = Env $ pure $ Left (Error "Undefined error") -// (<|>) f g = f >>= \ef -> g >>= \eg -> Env $ pure $ case ef of -// Left e = eg -// Right r = Right r - -instance Monad Env where - bind e f = e >>= \ee -> Env $ pure $ case ee of - (Left e) = Left e - (Right r) = f r - -get = state $ \s -> (s,s) +get = gets id instance toString SemError where toString (ParseError p e) = concat [ @@ -52,25 +35,23 @@ instance toString SemError where "SemError: Cannot unify types. Expected: ", toString t1, ". Given: ", toString t2] -sem :: AST -> SemOutput -sem x = undef -/* putIdent :: String Type -> Env Void -putIdent i t = gets ('Map'.get i) >>= \mt -> case mt of +putIdent i t = undef +/*putIdent i t = gets ('Map'.get i) >>= \mt -> case mt of Nothing = pure <$> modify ('Map'.put i t) Just t2 = unify t t2 >>= \r -> case r of Left e = pure $ Left e - Right t3 = pure <$> modify ('Map'.put i t3) + Right t3 = pure <$> modify ('Map'.put i t3)*/ sem :: AST -> SemOutput -sem (AST vd fd) -# (eithervds, gamma) = runState (mapM semVarDecl vd) 'Map'.newMap -# (eitherfds, gamma) = runState (mapM semFunDecl fd) gamma -= case splitEithers eithervds of - (Left errs) = Left $ errs ++ [x\\(Left x)<-eitherfds] - (Right vds) = case splitEithers eitherfds of - (Left errs) = Left errs - (Right fds) = Right $ AST vds fds +sem (AST vd fd) = case evalStateT m 'Map'.newMap of + Left e = Left [e] + Right (vds, fds) = Right (AST vds fds) +where + m :: Env (([VarDecl], [FunDecl])) + m = (mapM semVarDecl vd) >>= \vds -> + mapM semFunDecl fd >>= \fds -> + pure (vds, fds) splitEithers :: [Either a b] -> Either [a] [b] splitEithers [] = Right [] @@ -78,23 +59,20 @@ splitEithers [Right x:xs] = splitEithers xs >>= \rest->Right [x:rest] splitEithers xs = Left $ [x\\(Left x)<-xs] semFunDecl :: FunDecl -> Env FunDecl -semFunDecl f = pure $ Right f +semFunDecl f = pure f semVarDecl :: VarDecl -> Env VarDecl -semVarDecl vd=:(VarDecl pos type ident ex) = unify type ex - >>= \et->case et of - Left err = pure $ Left err - Right t = putIdent ident t >>| pure (Right $ VarDecl pos t ident ex) +semVarDecl (VarDecl pos type ident ex) = unify type ex + >>= \t-> putIdent ident t >>| (pure $ VarDecl pos t ident ex) typeExpr :: Expr -> Env Type -typeExpr (IntExpr _ _) = pure $ Right IntType -typeExpr (CharExpr _ _) = pure $ Right CharType -typeExpr (BoolExpr _ _) = pure $ Right BoolType +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 - >>= \ete1->typeExpr e2 >>= \ete2->pure ( - ete1 >>= \te1->ete2 >>= \te2->Right $ TupleType (te1, te2)) + >>= \t1-> typeExpr e2 >>= \t2-> pure $ TupleType (t1, t2) //Int typeExpr (Op2Expr p e1 BiPlus e2) = unify IntType e1 >>| unify IntType e2 typeExpr (Op2Expr p e1 BiMinus e2) = unify IntType e1 >>| unify IntType e2 @@ -122,25 +100,24 @@ typeExpr (Op2Expr p e1 BiCons e2) = undef class unify a :: Type a -> Env Type instance unify Expr where - unify (_ ->> _) e = pure $ Left $ ParseError (extrPos e) + unify (_ ->> _) e = liftT $ Left $ ParseError (extrPos e) "Expression cannot be a higher order function. Yet..." - unify VoidType e = pure $ Left $ ParseError (extrPos e) + unify VoidType e = liftT $ Left $ ParseError (extrPos e) "Expression cannot be a Void type." - unify (IdType _) e = pure $ Left $ ParseError (extrPos e) + unify (IdType _) e = liftT $ Left $ ParseError (extrPos e) "Expression cannot be an polymorf type." unify VarType e = typeExpr e - unify t e = typeExpr e - >>= \eithertype->case eithertype of - Left e = pure $ Left e - Right tex = unify t tex >>= \eitherun->case eitherun of - Left err = pure $ Left $ decErr e err - Right t = pure $ Right t + //we have to cheat to decorate the error, can be done nicer? + 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 $ Right IntType - unify BoolType BoolType = pure $ Right BoolType - unify CharType CharType = pure $ Right CharType - unify t1 t2 = pure $ Left $ UnifyError zero t1 t2 + unify IntType IntType = pure IntType + unify BoolType BoolType = pure BoolType + unify CharType CharType = pure CharType + unify t1 t2 = liftT $ Left $ UnifyError zero t1 t2 instance zero Pos where zero = {line=0,col=0} @@ -150,6 +127,10 @@ decErr e (UnifyError _ t1 t2) = UnifyError (extrPos e) t1 t2 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 @@ -159,5 +140,4 @@ extrPos (CharExpr p _) = p extrPos (BoolExpr p _) = p extrPos (FunExpr p _) = p extrPos (EmptyListExpr p) = p -extrPos (TupleExpr p _) = p -*/ \ No newline at end of file +extrPos (TupleExpr p _) = p \ No newline at end of file -- 2.20.1