မေႃႇၵျူး:No globals

This module causes an error if any nil global variable is read, or if any global is written to, with the exception of arg. To use, add require('Module:No globals') to the top of the module you wish to use it. The arg variable is excluded because it is necessary for Scribunto's require function to work properly. (See the relevant Scribunto source code here.)

---

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)