Module:No globals/sandbox
 | This is the module sandbox page for Module:No globals (diff). See also the companion subpage for test cases (run). |
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 | 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. |
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| 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)