Module:Protect
From The Kodiak Republic Wiki
This module is subject to page protection. It is a highly visible module in use by a very large number of pages, or is substituted very frequently. Because vandalism or mistakes would affect many pages, and even trivial editing might cause substantial load on the servers, it is protected from editing. |
This Lua module is used in system messages. Changes to it can cause immediate changes to the Wikipedia user interface. To avoid major disruption, any changes should be tested in the module's /sandbox or /testcases subpages, or in your own module sandbox. The tested changes can be added to this page in a single edit. Please discuss changes on the talk page before implementing them. |
This metamodule simplifies error handling in other modules. It transforms a function, which may throw an error, into a function, which returns a specified error message in that case.
Usage
local protect = require('Module:Protect')
local protectedFunc = protect(func, errFormat, options)
Arguments
func
- Function to be transformed.
errFormat
(default:'Error: %s'
)- Custom error message.
- Use
'%s'
to include the message from a caught error.
options
– optional table with the following fields:raw
(default: false)- If true, then
errFormat
will be used as is, otherwise it will be wrapped inside a tag<strong class="error">
.
- If true, then
removeLocation
(default: true)- If true, removes location information from caught error messages.
Return value
The resulting protectedFunc
is a function, which calls the original function func
, passing all arguments to it, and returns all its return values. If func
throws an error, the specified error message is returned instead.
Example
local protect = require('Module:Protect')
local p = {}
function p.main(frame)
if not frame.args[1] then
error('missing argument')
end
return frame.args[1]
end
p.main = protect(p.main)
return p
Invoking the main function without arguments will output: Error: missing argument
local function processResult(options, success, ...)
if not success then
local message = tostring(... or '(no message)')
if options.removeLocation then
message = string.gsub(message, '^Module:[^:]+:%d+: ', '', 1)
end
return string.format(options.errFormat, message)
end
return ...
end
local function protect(func, errFormat, options)
if type(errFormat) == 'table' then
options = options or errFormat
errFormat = nil
end
options = mw.clone(options) or {}
options.errFormat = errFormat or options.errFormat or 'Error: %s'
if not options.raw then
options.errFormat = '<strong class="error">' .. options.errFormat .. '</strong>'
end
options.removeLocation = options.removeLocation == nil or options.removeLocation
return function (...)
return processResult(options, pcall(func, ...))
end
end
return protect