diff --git a/RosettaParser.cabal b/RosettaParser.cabal
index ce0482e..34cf789 100644
--- a/RosettaParser.cabal
+++ b/RosettaParser.cabal
@@ -40,6 +40,7 @@ library
       PrettyPrinter.RosettaObject
       PrettyPrinter.Type
       Semantic.ExpressionChecker
+      Semantic.FunctionChecker
       Semantic.TypeChecker
   other-modules:
       Paths_RosettaParser
diff --git a/app/Main.hs b/app/Main.hs
index aba9e81..c18fa35 100644
--- a/app/Main.hs
+++ b/app/Main.hs
@@ -12,6 +12,7 @@ import PrettyPrinter.Type
 import PrettyPrinter.Function
 import Semantic.TypeChecker
 import Semantic.ExpressionChecker
+import Semantic.FunctionChecker
 import Model.Function
 import Model.Type
 import System.Environment.Blank (getArgs)
@@ -26,7 +27,7 @@ main = do
     case parse rosettaParser "" (Text.pack rosettaString) of
         Left errorBundle -> print (errorBundlePretty errorBundle)
         Right objs -> do
-            putStrLn $ printObjects (definedTypes, definedFunctions) objs
+            writeFile (args !! 1) (printObjects (definedTypes, definedFunctions) objs) 
             where 
                 definedFunctions = addNewFunctions (definedTypes, defaultMap) objs
                 definedTypes = addNewTypes [] objs
@@ -39,15 +40,15 @@ printObjects (t, s) objs
                     
 printObject :: ([Type], [Symbol]) -> RosettaObject -> Either [TypeCheckError] String
 printObject (definedTypes, _) (TypeObject t)
-    | isRight checked = Right $ printType t
+    | isRight checked = Right $ printType $ fromRightUnsafe checked
     | otherwise = Left $ fromLeftUnsafe checked
     where checked = checkType definedTypes t
 printObject _ (EnumObject e) = Right $ printEnum e
-printObject (_, definedFunctions) (FunctionObject (MakeFunction name desc inp out ex))
-    | isRight checked = Right $ printFunction (MakeFunction name desc inp out ex)
-    | otherwise = Left [fromLeftUnsafe checked]
+printObject (definedTypes, definedFunctions) (FunctionObject fun)
+    | isRight checked = Right $ printFunction $ fromRightUnsafe checked
+    | otherwise = Left $ fromLeftUnsafe checked
     where 
-        checked = checkExpression definedFunctions ex
+        checked = checkFunction (definedTypes, definedFunctions) fun
 
 addNewFunctions :: ([Type], [Symbol]) -> [RosettaObject] -> [Symbol]
 addNewFunctions (_, s) [] = s
diff --git a/src/PrettyPrinter/Function.hs b/src/PrettyPrinter/Function.hs
index b72090f..c573600 100644
--- a/src/PrettyPrinter/Function.hs
+++ b/src/PrettyPrinter/Function.hs
@@ -24,9 +24,9 @@ printExpression (Parens ex) = "(" <> printExpression ex <> ")"
 printExpression (List ex) = list (map printExpression ex)
 printExpression (Function name ex) = pretty name <> tupled (map printExpression ex) 
 printExpression (PrefixExp name ex) = pretty name <+> printExpression ex
-printExpression (PostfixExp name ex) = printExpression ex <+> pretty name
+printExpression (PostfixExp name ex) = pretty name <+> printExpression ex
 printExpression (InfixExp name ex1 ex2) = printExpression ex1 <+> pretty name <+> printExpression ex2
-printExpression (IfSimple cond ex) = "if" <+> printExpression cond <+> "then" <+> printExpression ex
+printExpression (IfSimple cond ex) = "if" <+> printExpression cond <+> "then" <+> printExpression ex <+> "else" <+> "pure ()"
 printExpression (IfElse cond ex1 ex2) = "if" <+> printExpression cond <+> "then" <+> printExpression ex1 <+> "else" <+> printExpression ex2
 
 printFunctionSignature :: Function -> Doc a
diff --git a/src/Semantic/FunctionChecker.hs b/src/Semantic/FunctionChecker.hs
new file mode 100644
index 0000000..c8e1134
--- /dev/null
+++ b/src/Semantic/FunctionChecker.hs
@@ -0,0 +1,16 @@
+module Semantic.FunctionChecker where
+
+import Model.Function
+import Model.Type
+import Semantic.ExpressionChecker
+import Semantic.TypeChecker
+import Data.Either
+
+checkFunction :: ([Type], [Symbol]) ->  Function -> Either [TypeCheckError] Function
+checkFunction (definedTypes, definedFunctions) (MakeFunction name desc inp out ex)
+    | isRight checkedEx && isRight checkedOut && null (lefts checkedIn) = Right $ MakeFunction name desc (rights checkedIn) (fromRightUnsafe checkedOut) ex
+    | otherwise = Left $ lefts [checkedOut] ++ lefts checkedIn ++ lefts [checkedEx]
+        where 
+            checkedEx = checkExpression definedFunctions ex
+            checkedIn = checkAttributes definedTypes inp
+            checkedOut = head $ checkAttributes definedTypes [out]
\ No newline at end of file