Created by maurtis150 on Facepunch. Adapt to your needs

local files = {}

function autoReload(fileName)
    files[fileName] = 0
end

function checkAutoReload()
    for k, v in pairs(files) do
        local t = file.Time(k, "LUA")

        if t then
            if files[k] != t then
                files[k] = t

                include(k)
            end
        else
            print("invalid file: ", k)
            files[k] = nil
        end
    end
end
timer.Create("checkAutoReload", 0.1, 0, checkAutoReload)

autoReload("simploo/simploo.lua")