Difference between revisions of "Module:No globals"

From Railway Operation Simulator Wiki
Jump to navigation Jump to search
m (1 revision imported)
m (1 revision imported)
 

Latest revision as of 19:51, 7 May 2021

Documentation for this module may be created at Module:No globals/doc

local mt = getmetatable(_G) or {}
function mt.__index (t, k)
	if k ~= 'arg' then
		error('Tried to read nil global ' .. tostring(k), 2)
	end
	return nil
end
function mt.__newindex(t, k, v)
	if k ~= 'arg' then
		error('Tried to write global ' .. tostring(k), 2)
	end
	rawset(t, k, v)
end
setmetatable(_G, mt)