Module:No globals

From BlazBlue Wiki
Revision as of 22:58, 11 February 2019 by Desu (talk | contribs) (Imported Module:No globals from Wikipedia ( https://en.wikipedia.org/wiki/Module:No_globals ))
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

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 using it. The arg variable is excluded because it is necessary for Scribunto's require function to work properly.

Template:Sandbox other


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)