Making an object nil

General
1

If I want to get rid of an object once and for all, can I just say:

self = nil

I trying this, but as far as I can tell, the object is still there. Is there anything else I can do to banish an object, so to speak?

2

This will work — however self is a special object.

For example, you might have method declared as follows:

function MyClass:myFunction(x, y, z)
    self.pos = vec3(x,y,z)
end

------------------
-- calling the method

obj = MyClass()
obj:myFunction( 1, 2, 3 )

```


In the context of the method function (i.e. `function MyClass:myFunction`) the keyword `self` is really referring to an argument. So setting it to nil will not really do anything.

E.g., the above code is similar to the following:


-- Notice how "self" is an argument
--  and the function is declared with a '.'
function MyClass.myFunction(self, x, y, z)
    self.pos = vec3(x,y,z)
end

------------------
-- calling the method
--  notice we pass 'obj' as the argument for 'self'

obj = MyClass()
obj.myFunction( obj, 1, 2, 3 )

```


So, if you really want to delete the object represented by `self`, set the actual object to `nil` — not `self`.
3

Here is a small example of destroying an object and setting it to nil. This draws a falling circle and when it reaches a y value of 300, the circle is destroyed.


function setup()
    c1=circle(400,800)
end

function draw()
    background(40, 40, 50)
    c1:draw()
end

circle=class()

function circle:init(x,y)
    self.c1=physics.body(CIRCLE,50)
    self.c1.x=x
    self.c1.y=y
end

function circle:draw()
    fill(255)
    if self.c1~=nil then
        ellipse(self.c1.x,self.c1.y,100)
        if self.c1.y<300 then
            self.c1:destroy()
            self.c1=nil
        end
    end
end
4

@Simeon thanks for explaining the keyword ‘self.’ It makes more sense now. At the end of your post you mentioned that I should delete the object represented by self. I’m not quite sure how to do this.
*For clarifation of my question, I don’t want to delete the whole class, just one item that is made from that class.

5

So in that case you could do it like this:

obj = MyClass()
obj:myFunction( 1, 2, 3 )

-- Later on...
obj = nil -- deletes 'obj'

```


Setting an object to nil will not delete it immediately, but it will delete it next time the garbage collection process is run.