Object destruction

[Sky Rider]

I've faced a weird problem: I cant destroy an object O_o
The thing is that I create almost every object as an instance of a class. So I cant set an object to nil directly, thats why I use such method:

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function physical:deinit()
	self = nil
end

But it doesnt work. I aslo tried:

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function physical:deinit()
	objList[self.id] = nil --objList contains all the objects, self.id as an index of an instance in the list
end

But it has no effect as well.
So how can I destroy an object?

[bartbes]

You remove all references.

If you're using love.physics (or possibly other physics engines), and you're witnessing the object staying in the simulation for a while, that's because garbage collection isn't instantaneous, love.physics has destroy methods on most objects, for this specific reason, and other physics engines might have similar methods.

[Sky Rider]

You remove all references.

Somewhy I dont. When, for example, I create an object "player"

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pl = player:new("EaJet", 250, 250, 180)

and then destroy it with

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self = nil

I can still access data in "pl" table, for eample, by drawing

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love.graphics.print(pl.module[1].x1, 25, 150)

Wth, "self = nil" should destroy the whole table

[kclanc]

self and pl, being local variables, are considered references. assigning self to nil just removes one reference; it does not affect the object being pointed to. Since pl is a reference and remains in tact, assigning self to nil does not remove all references to your object.

[Robin]

Wth, "self = nil" should destroy the whole table

No, it only changes a single reference. There's still at least one other reference: the pl table. You need to bind nil to that name as well (and make sure it doesn't try to draw the player if pl is nil).

[Sky Rider]

Of course, pl = nil solves all the problems But, for example, for bullets I have such code:

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if love.mouse.isDown("l") then
	bullet:new(hostPlayer) --hostPlayer is a parent object
end

So bullet:new does return a table, but it is ignored. Instead, bullet is added to objList:

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table.insert(objList, self)
self.id = table.maxn(objList)

and then, when its time to destroy a bullet (it comes after 1.5s of life), I simply remove it from the table:

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table.remove(objList, self.id)
-- shifting ids of other objects:
for j = self.id + 1, table.maxn(objList) do
	objList[j].id = objList[j].id - 1
end
self = nil

But memory doesnt seem to be freed. In fact, with every new bullet the game consumes more and more memory despite the fact, that every bullet lives 1.5s.

[kclanc]

If all references have been removed, the memory will not be freed until garbage collection happens. Calling collectgarbage("collect") will trigger this. http://www.lua.org/manual/5.1/manual.html#2.10

[Sky Rider]

Even calling collectgarbage("collect") in update function doesn't help. I guess there are some references I've forgotten about. Gonna check it tomorrow. Thanks