game = {updates = {}, running = false}

function game:update ()
    self.numupdates = 0
    for i, v in pairs(self.updates) do
        self.numupdates = self.numupdates + 1
        v(self)
    end
end

function game:run ()
    self.isrunning = true
    repeat
        self:update()
    until self.numupdates == 0
    self.isrunning = false
end

do
    local times = 10
    function game.updates:test ()
        print(times)
        times = times - 1
        if times == 0 then
            game.updates.test = nil
        end
    end
end

game:run()
--[[
10
9
8
7
6
5
4
3
2
1
]]