-semVarDecl v = pure $ Right v
-//Right v
-//semVarDecl vd=:(VarDecl pos type ident expr) = case unify type expr of
-// Left e = Left e
-// //TODO ident in de environment
-// Right e = Right $ pure vd
-//
-//typeExpr :: Expr -> Env Type
-//typeExpr (IntExpr _ _) = Right $ pure IntType
-//typeExpr (CharExpr _ _) = Right $ pure CharType
-//typeExpr (BoolExpr _ _) = Right $ pure BoolType
-//typeExpr (Op1Expr p UnNegation expr) = undef//typeExpr expr
-//// >>= \exprtype->case exprtype of
-//// Right BoolType = Right $ pure BoolType
-//// t = Left $ UnifyError p BoolType exprtype
-//typeExpr (Op1Expr p UnMinus expr) = undef// typeExpr expr
-//// >>= \exprtype->case exprtype of
-//// IntType = Right $ pure IntType
-//// t = Left $ UnifyError p IntType exprtype
-//// typeExpr (Op2Expr Pos Expr Op2 Expr) = undef
-////typeExpr (FunExpr Pos FunCall
-////typeExpr (EmptyListExpr Pos
-////typeExpr (TupleExpr Pos (Expr, Expr)
-////typeExpr (VarExpr Pos VarDef) = undef
-////
-//class unify a :: Type a -> Env a
-//
-//instance unify Type where
-// unify IntType IntType = Right $ pure IntType
-// unify BoolType BoolType = Right $ pure BoolType
-// unify CharType CharType = Right $ pure CharType
-// unify _ _ = undef
-//
-//instance unify Expr where
-// unify type expr = case type of
-// _ ->> _ = Left $ ParseError (extrPos expr)
-// "Expression cannot be a higher order function. Yet..."
-// VoidType = Left $ ParseError (extrPos expr)
-// "Expression cannot be a Void type."
-// IdType _ = Left $ ParseError (extrPos expr)
-// "Expression cannot be an polymorf type."
-// TupleType (_, _) = undef
-// ListType _ = undef
-// IntType = undef
-// BoolType = undef
-// CharType = undef
-// VarType = undef
-//
-//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
+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 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)
+//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) = undef
+typeExpr (Op2Expr p e1 BiUnEqual e2) = undef
+//char of int
+typeExpr (Op2Expr p e1 BiLesser e2) = undef
+typeExpr (Op2Expr p e1 BiGreater e2) = undef
+typeExpr (Op2Expr p e1 BiLesserEq e2) = undef
+typeExpr (Op2Expr p e1 BiGreaterEq e2) = undef
+//bool
+typeExpr (Op2Expr p e1 BiAnd e2) = undef
+typeExpr (Op2Expr p e1 BiOr e2) = undef
+//a
+typeExpr (Op2Expr p e1 BiCons e2) = undef
+//typeExpr (FunExpr Pos FunCall) = undef
+//typeExpr (EmptyListExpr Pos) = undef
+//typeExpr (VarExpr Pos VarDef) = undef //when checking var-expr, be sure to put the infered type
+ //in the context
+
+class unify a :: Type a -> Env Type
+
+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 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 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 (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
\ No newline at end of file