fixed an issue with forNode's checkType

LineNodes.py

@@ -450,11 +450,14 @@ class ForNode(ASTNode):
         self.children.append(self.bodyStatement)
 
     def checkType(self):
-        self.forInit.checkType()
-        self.forBound.checkType()  # need resolving var declared in forInit to use it in forBound
-        if self.forBound.myType.name != 'boolean':
-            raise Exception("ERROR: Cannot use non-boolean type for forBound.")
-        self.forUpdate.checkType()
+        if self.forInit:
+            self.forInit.checkType()
+        if self.forBound:
+            self.forBound.checkType()  # need resolving var declared in forInit to use it in forBound
+            if self.forBound.myType.name != 'boolean':
+                raise Exception("ERROR: Cannot use non-boolean type for forBound.")
+        if self.forUpdate:
+            self.forUpdate.checkType()
         self.bodyStatement.checkType()
 
     def reachCheck(self, inMaybe):