Module:No globals: Difference between revisions

(Created page with "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.__newi...")
m (4 revisions imported from wikipedia:Module:No_globals: see Topic:Vtixlm0q28eo6jtf)
 
(15 intermediate revisions by 13 users not shown)
(No difference)

Latest revision as of 11:43, 21 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)