toString (ParseError p e) = concat [
toString p,"SemError: ParseError: ", e]
toString (Error e) = "SemError: " +++ e
- toString (UnifyErrorStub t1 t2) = toString (UnifyError {line=0,col=0} t1 t2)
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]
sem :: AST -> SemOutput
sem (AST vd fd) = case runStateT m ('Map'.newMap, getRandomStream 1) of
semVarDecl (VarDecl pos type ident ex) = unify type ex
>>= \t-> putIdent ident t >>| (pure $ VarDecl pos t ident ex)
+typeOp2 :: Expr Expr Op2 [Type] -> Env Type
+typeOp2 e1 e2 op ts = typeExpr e1 >>= \t1-> typeExpr e2 >>= \t2->
+ unify t1 t2 >>= \t3->if (isMember t3 ts) (pure t3)
+ (liftT $ Left $ OperatorError (extrPos e1) op t3)
+
typeExpr :: Expr -> Env Type
typeExpr (IntExpr _ _) = pure IntType
typeExpr (CharExpr _ _) = pure CharType
typeExpr (Op1Expr p UnMinus expr) = unify IntType expr
typeExpr (TupleExpr p (e1, e2)) = typeExpr e1
>>= \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
-typeExpr (Op2Expr p e1 BiTimes e2) = unify IntType e1 >>| unify IntType e2
-typeExpr (Op2Expr p e1 BiDivide e2) = unify IntType e1 >>| unify IntType e2
-typeExpr (Op2Expr p e1 BiMod e2) = unify IntType e1 >>| unify IntType e2
-//bool, char of int
-typeExpr (Op2Expr p e1 BiEquals e2) = typeExpr e1 >>= \t1 -> unify t1 e2
- >>| pure BoolType //todo, actually check t1 in Char,Bool,Int
-typeExpr (Op2Expr p e1 BiUnEqual e2) = typeExpr (Op2Expr p e1 BiEquals e2)
-//char of int
-typeExpr (Op2Expr p e1 BiLesser e2) = typeExpr e1 >>= \t1 -> unify t1 e2
- >>| pure BoolType //todo, actually check t1 in Char, Int
-typeExpr (Op2Expr p e1 BiGreater e2) = typeExpr (Op2Expr p e1 BiLesser e2)
-typeExpr (Op2Expr p e1 BiLesserEq e2) = typeExpr (Op2Expr p e1 BiLesser e2)
-typeExpr (Op2Expr p e1 BiGreaterEq e2) = typeExpr (Op2Expr p e1 BiLesser e2)
-//bool
-typeExpr (Op2Expr p e1 BiAnd e2) = unify BoolType e1 >>| unify BoolType e2
-typeExpr (Op2Expr p e1 BiOr e2) = unify BoolType e1 >>| unify BoolType e2
-//a
-typeExpr (Op2Expr p e1 BiCons e2) = typeExpr e1 >>= \t1-> typeExpr e2
- >>= \t2-> unify (ListType t1) t2
+typeExpr (Op2Expr p e1 op e2)
+| isMember op [BiPlus, BiMinus, BiTimes, BiDivide, BiMod] =
+ typeOp2 e1 e2 op [IntType]
+| isMember op [BiEquals, BiUnEqual] =
+ typeOp2 e1 e2 op [IntType, BoolType, CharType]
+| isMember op [BiLesser, BiGreater, BiLesserEq, BiGreaterEq] =
+ typeOp2 e1 e2 op [IntType, CharType]
+| isMember op [BiAnd, BiOr] =
+ typeOp2 e1 e2 op [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) = undef
-//typeExpr (VarExpr Pos VarDef) = undef //when checking var-expr, be sure to
- //put the infered type in the context
+typeExpr (FunExpr p (FunCall fid args)) = undef
+//ignore field selectors
+typeExpr (VarExpr p (VarDef ident fs)) = gets (\(st, r)->'Map'.get ident st)
+ >>= \mt->case mt of
+ Nothing = let t = IdType ident in putIdent ident t >>| pure t
+ Just t = unify t fs
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 (IdType _) e = liftT $ Left $ ParseError (extrPos e)
"Expression cannot be an polymorf type."
unify VarType e = typeExpr e
+ unify (IdType i) e = undef
//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
-
+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 unify Type where
unify IntType IntType = pure IntType
unify BoolType BoolType = pure BoolType
unify CharType CharType = pure CharType
- //unify t (IdType i) = unify (IdType i) t
- //note, don't use putIdent as that will call unify again
- //unify (IdType i) e=:(IdType j) = modify (\(st, r)->('Map'.put j e st, r))
- //unify (ListType t1) (ListType t2) = unify t1 t2
+ 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 t1 t2 = liftT $ Left $ UnifyError zero t1 t2
instance zero Pos where
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
instance toString Gamma where
toString (mp, _) = concat
[concat [k, ": ", toString v, "\n"]\\(k, v) <- 'Map'.toList mp]
+
+
+// class free a :: a -> Env [a]
repositories / cc1516.git / blobdiff