Module:No globals: Difference between revisions

From Zoophilia Wiki
Jump to navigationJump to search
meta>Ged UK
m (Protected Module:No globals: High-risk Lua module ([Edit=Allow only template editors and admins] (indefinite) [Move=Allow only template editors and admins] (indefinite)))
m (9 revisions imported)
 
(6 intermediate revisions by 5 users not shown)
Line 1: Line 1:
local mt = getmetatable(_G) or {}
local mt = getmetatable(_G) or {}
function mt.__index (t, k)
function mt.__index (t, k)
if k ~= 'name' and k ~= 'arg' then
if k ~= 'arg' then
error('Tried to read nil global ' .. tostring(k), 2)
error('Tried to read nil global ' .. tostring(k), 2)
end
end

Latest revision as of 00:52, 3 September 2020

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 <syntaxhighlight lang="lua" inline>require('Module:No globals')</syntaxhighlight> 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


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)