【Lua实战】闭包封装状态：计数器与工厂函数的实战应用

local function newCounter(start)
    local count = start or 0
    local function add(step)
        count = count + (step or 1)
        return count
    end
    local function value()
        return count
    end
    return add, value
end
local addKill, getKills = newCounter(0)
function killmon(actor)
    addKill(1)
    if getKills() >= 500 then
        addKill(-500)
        giveitem(actor, "屠魔证书", 1)
    end
end

local function newLimiter(limit, window)
    local log = {}
    return function(now)
        for i = #log, 1, -1 do
            if now - log[i] > window then
                table.remove(log, i)
            end
        end
        if #log >= limit then
            return false
        end
        table.insert(log, now)
        return true
    end
end
local tradeAllow = newLimiter(5, 300)