Module:No globals
Revision as of 00:52, 19 February 2021 by Mediawiki>Magog the Ogre (4 revisions imported from w:en:Module:No_globals)
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This module causes an error if any nil global 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. (See the Scribunto source code here.)
See also
- Module:Log globals – adds all nil global reads/writes to the Lua log
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)