Module:No globals

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Usage

Include this module at the top of your code. An error will be raised any time your code tries to read or write to a non-local (undeclared) variable.

The above documentation is transcluded from Module:No globals/doc. (Edit | History)
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---

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)