-- lua对象序列化
function serialize(obj)
    local lua = ""
    local t = type(obj)
    if t == "number" then
        lua = lua .. obj
    elseif t == "boolean" then
        lua = lua .. tostring(obj)
    elseif t == "string" then
        lua = lua .. string.format("%q", obj)
    elseif t == "table" then
        lua = lua .. "{\n"
        for k, v in pairs(obj) do
            lua = lua .. "[" .. serialize(k) .. "]=" .. serialize(v) .. ",\n"
        end
        local metatable = getmetatable(obj)
        if metatable ~= nil and type(metatable.__index) == "table" then
            for k, v in pairs(metatable.__index) do
                lua = lua .. "[" .. serialize(k) .. "]=" .. serialize(v) .. ",\n"
            end
        end
        lua = lua .. "}"
    elseif t == "nil" then
        return nil
    else
        error("can not serialize a " .. t .. " type.")
    end
    return lua
end
setfenv(serialize, {type = _G.type, tostring = _G.tostring, error = _G.error})

-- lua对象反序列化
function unserialize(lua)
    local t = type(lua)
    if t == "nil" or lua == "" then
        return nil
    elseif t == "number" or t == "string" or t == "boolean" then
        lua = tostring(lua)
    else
        error("can not unserialize a " .. t .. " type.")
    end
    lua = "return " .. lua
    local func = loadstring(lua)
    if func == nil then return nil end
    return func()
end
setfenv(unserialize, {type = _G.type, tostring = _G.tostring, error = _G.error, loadstring = _G.loadstring})