local function makeEnum(enumtable)
	if enumtable == nil or type(enumtable) ~= "table" then 
		return nil
	end 
	enumtable.__index = enumtable 
	enumtable.__newindex = function() 
		print("can not modify enum")
	end 
	local e = {}
	setmetatable(e, enumtable)
	return e
end

local function main() 
	local mode = makeEnum({
		SinglePlayer = 1, 
		TwoPlayers= 2,
		ThreePlayers= 3, 
		FourPlayers= 4,
		PVCom= 5,
	})
	mode.SinglePlayer = 2
	print(mode.SinglePlayer)
end 

main()