Attempt to perform arithmetic on field 'y' (a nil value)?

Getting Started Newbie Questions
#1

The error is happening on the second line! Whats going on? I need to be able to remove Self

Attempt to perform arithmetic on field ‘y’ (a nil value) 

 local function backgroundScroll(self,event) self.y = self.y - self.speed if self.y \> W1\*0.2 then display.remove(self) end end Runtime:addEventListener("enterFrame", myCircle) myCircle.enterFrame=backgroundScroll
#2

You can’t pass a table listener to an enterFrame event. It should be a discrete function.

http://coronalabs.com/blog/2012/02/21/understanding-coronas-enterframe-event/

#3

You can’t pass a table listener to an enterFrame event. It should be a discrete function.

http://coronalabs.com/blog/2012/02/21/understanding-coronas-enterframe-event/