-typeExpr (IntExpr _ _) = pure $ Right IntType
-typeExpr (CharExpr _ _) = pure $ Right CharType
-typeExpr (BoolExpr _ _) = pure $ Right BoolType
-typeExpr (Op1Expr p UnNegation expr) = typeExpr expr
- >>= \exprtype->case exprtype of
- Left e = pure $ Left e
- Right BoolType = pure $ Right BoolType
- Right (IdType ident) = putIdent ident BoolType >>| pure (Right BoolType)
- Right t = pure $ Left $ UnifyError p BoolType t
-//typeExpr (Op1Expr p UnMinus expr) = typeExpr expr
-// >>= \exprtype->case exprtype of
-// IntType = pure $ Right IntType
-// t = Left $ UnifyError p IntType exprtype
-//typeExpr (Op2Expr Pos Expr Op2 Expr) = undef
+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