用Lua的协程实现类似Unity协程的语句块

 local co_time_tbl = {}
 setmetatable(co_time_tbl, { __len = function(o)
     local count =
     for k, v in pairs(o) do
         count = count +
     end
     return count
 end
 })

 local function isWindows()
     return package.config:sub(, ) == "\\"
 end

 local function sleep(n)
     if isWindows() then
         if n >  then
             os.execute("ping -n " .. tonumber(n + ) .. " localhost > NUL")
         end
     else
         os.execute("sleep " .. tonumber(n))
     end
 end

 local function Update(deltaTime)
     -- main loop
 end

 local function updateCoroutine()
     local iTime = os.time()
     for kco, vTime in pairs(co_time_tbl) do
         if iTime >= vTime then
             if coroutine.status(kco) == "suspended" or coroutine.status(kco) == "normal" then
                 coroutine.resume(kco)
             elseif coroutine.status(kco) == "dead" then
                 co_time_tbl[kco] = nil
             end
         end
     end
 end

 function coroutine.waitforSeconds(second)
     assert(type(second) == "number" or second <= )
     local iEndTime = os.time() + second
     local co = coroutine.running()
     if co then
         co_time_tbl[co] = iEndTime
         return coroutine.yield()
     end
 end

 local function main()
     local co1 = coroutine.wrap(function()
         coroutine.waitforSeconds()
         print("after 5 seconds")
     end)
     local co2 = coroutine.wrap(function()
         coroutine.waitforSeconds()
         print("after 4 seconds")
     end)
     local co3 = coroutine.wrap(function()
         coroutine.waitforSeconds()
         print("after 3 seconds")
     end)
     local count =
     local co4 = coroutine.wrap(function()
         while (true) do
             coroutine.waitforSeconds()
             count = count +
             print("coroutine num: " .. #co_time_tbl .. " | second count:" .. count)
         end
     end)
     co1()
     co2()
     co3()
     co4()
     while true do
         sleep(0.033)
         Update()
         updateCoroutine()
     end
 end

 main()

思路其实就是用一张表维护协程要等待的时间，在主循环之后更新计时器，根据时间将挂起的协程唤醒就行