Module:No globals
Appearance
Warning: | This page is shared between multiple wikis. All changes to this page will be automatically copied to all wikis listed in the left side bar. To avoid unnecessary page regeneration and server load, changes should be tested on the page's sandbox. Please help translate this page. |
This module is rated as ready for general use. It has reached a mature form and is thought to be bug-free and ready for use wherever appropriate. It is ready to mention on help pages and other resources as an option for new users to learn. To reduce server load and bad output, it should be improved by sandbox testing rather than repeated trial-and-error editing. |
This module is subject to page protection. It is a highly visible module in use by a very large number of pages. Because vandalism or mistakes would affect many pages, and even trivial editing might cause substantial load on the servers, it is protected from editing. |
TNT | This module uses Module:TNT for localisation: |
This module is deprecated in most use cases, use strict library: require( "strict" )
.
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.
Tests
Module:No globals | success: 1, error: 0, skipped: 0 |
Module:No globals/sandbox | success: 1, error: 0, skipped: 0 |
- See test cases
- Diff sandbox code
local mt = getmetatable(_G) or {}
function mt.__index (t, k)
if k ~= 'arg' then
-- perf optimization here and below: do not load Module:TNT unless there is an error
error(require('Module:TNT').format('I18n/No globals', 'err-read', tostring(k)), 2)
end
return nil
end
function mt.__newindex(t, k, v)
if k ~= 'arg' then
error(require('Module:TNT').format('I18n/No globals', 'err-write', tostring(k)), 2)
end
rawset(t, k, v)
end
setmetatable(_G, mt)