-//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
+typeExpr :: Expr -> Env Type
+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 (FunExpr Pos FunCall) = undef
+//typeExpr (EmptyListExpr Pos) = undef
+//typeExpr (TupleExpr Pos (Expr, Expr)) = undef
+//typeExpr (VarExpr Pos VarDef) = undef
+
+
+