Easy task lock

Interlock.lua

--[[
local fooInterlock = Interlock.new()

function foo()
	local lock = fooInterlock:takeLock()

	coroutine.yield()
	
	if not lock:hasLock() then
		return
	end

	bar()
end
--]]

local LocalLock = {} do
	LocalLock.__index = LocalLock
	
	function LocalLock.new(lock)
		return setmetatable({
			_parent = lock,
			_localState = lock._state,
		}, LocalLock)
	end
	
	function LocalLock:hasLock()
		return self._localState == self._parent._state
	end
end

local Interlock = {} do
	Interlock.__index = Interlock
	
	function Interlock.new()
		return setmetatable({
			_state = 0,
		}, Interlock)
	end
	
	function Interlock:takeLock()
		self._state = (self._state + 1)%2^53
		return LocalLock.new(self)
	end
end

return Interlock