Module:Redirect
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| 40x40px | This module is rated as beta, and is ready for widespread use. It is still new and should be used with some caution to ensure the results are as expected. |
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This module contains functions to find the target of a redirect page.
Contents
Main
The main function accepts the name of a single page. It determines if the page is a redirect; if so it looks up the page, extracts the target, and returns the target name as text. Its usage is {{#invoke:redirect|main|redirect-page-name}}.
The template normally neither takes nor gives square brackets, so to show the result as a link use [[{{#invoke:redirect|main|redirect-page-name}}]]. An error is produced if the redirect does not exist, but for versatility no error is given if the file is not a redirect (returns the original text) or if the file name is blank (returns blank).
However, if the parameter bracket is given a nonblank value, brackets will be passed on if present.
Examples
-
{{#invoke:redirect|main|WP:AFC}}→ WP:AFC -
{{#invoke:redirect|main|[[WP:AFD]]|bracket=yes}}→ WP:AFD -
{{#invoke:redirect|main|Wikipedia:Articles for deletion}}→ wikipedia:Articles for deletion
Note: WP:AFC and WP:AFD are both redirects, but Wikipedia:Articles for deletion is not.
LuaMain
If you want to use the main function from another Lua module, you may want to use the luaMain function. This provides the same functionality as the main function, but doesn't require that a frame object be available.
To use this, first load the module.
<source lang="lua"> local mRedirect = require('Module:Redirect') </source>
Then use the function with the following syntax:
<source lang="lua"> mRedirect.luaMain(rname, bracket) </source>
rname is the name of the redirect page, and if bracket is anything but false or nil, the module will produce a link rather than just a page name.
IsRedirect
The isRedirect function is used from wiki pages to find out if a given page is a redirect or not. If the page is a redirect, the function returns "yes", and if not the output is blank. Its usage is {{#invoke:redirect|isRedirect|redirect-page-name}}.
Examples
-
{{#invoke:redirect|isRedirect|WP:AFC}}→ -
{{#invoke:redirect|isRedirect|Wikipedia:Articles for deletion}}→
LuaIsRedirect
The isRedirect can be accessed from other Lua modules in the same way as the main function:
<source lang="lua"> local mRedirect = require('Module:Redirect') mRedirect.luaIsRedirect(rname) </source>
GetTarget
The getTarget function fetches the target page name of a redirect page, and is only usable from Lua. If the page specified is a redirect, then the target is returned; otherwise the function returns nil.
To use it, first load the module.
<source lang="lua"> local mRedirect = require('Module:Redirect') </source>
Then use the function with the following syntax:
<source lang="lua"> mRedirect.getTarget(page) </source>
page can be either the name of the redirect page as a string, or a mw.title object.
See also
- bugzilla:66974 - Provide a standard way to get the target of a redirect page
- mw:Extension:Scribunto/Lua reference manual#Title objects, the Scribunto interface for determining a page's redirect status
- Template:Submit an edit request, which uses this module
-- This module provides functions for getting the target of a redirect page.
local p = {}
-- Gets a mw.title object, using pcall to avoid generating script errors if we
-- are over the expensive function count limit (among other possible causes).
local function getTitle(...)
local success, titleObj = pcall(mw.title.new, ...)
if success then
return titleObj
else
return nil
end
end
-- Gets the name of a page that a redirect leads to, or nil if it isn't a
-- redirect.
function p.getTargetFromText(text)
return string.match(
text,
"^%s*#[Rr][Ee][Dd][Ii][Rr][Ee][Cc][Tt]%s*:?%s*%[%[([^%[%]|]-)%]%]"
) or string.match(
text,
"^%s*#[Rr][Ee][Dd][Ii][Rr][Ee][Cc][Tt]%s*:?%s*%[%[([^%[%]|]-)|[^%[%]]-%]%]"
)
end
-- Gets the target of a redirect. If the page specified is not a redirect,
-- returns nil.
function p.getTarget(page, fulltext)
-- Get the title object. Both page names and title objects are allowed
-- as input.
local titleObj
if type(page) == 'string' or type(page) == 'number' then
titleObj = getTitle(page)
elseif type(page) == 'table' and type(page.getContent) == 'function' then
titleObj = page
else
error(string.format(
"bad argument #1 to 'getTarget'"
.. " (string, number, or title object expected, got %s)",
type(page)
), 2)
end
if not titleObj or not titleObj.isRedirect then
return nil
end
-- Find the target by using string matching on the page content.
local target = p.getTargetFromText(titleObj:getContent() or "")
if target then
local targetTitle = getTitle(target)
if targetTitle then
if fulltext then
return targetTitle.fullText
else
return targetTitle.prefixedText
end
else
return nil
end
else
-- The page is a redirect, but matching failed. This indicates a bug in
-- the redirect matching pattern, so throw an error.
error(string.format(
'could not parse redirect on page "%s"',
fulltext and titleObj.fullText or titleObj.prefixedText
))
end
end
--[[
-- Given a single page name determines what page it redirects to and returns the
-- target page name, or the passed page name when not a redirect. The passed
-- page name can be given as plain text or as a page link.
--
-- Returns page name as plain text, or when the bracket parameter is given, as a
-- page link. Returns an error message when page does not exist or the redirect
-- target cannot be determined for some reason.
--]]
function p.luaMain(rname, bracket, fulltext)
if type(rname) ~= "string" or not rname:find("%S") then
return nil
end
bracket = bracket and "[[%s]]" or "%s"
rname = rname:match("%[%[(.+)%]%]") or rname
local target = p.getTarget(rname, fulltext)
local ret = target or rname
ret = getTitle(ret)
if ret then
if fulltext then
ret = ret.fullText
else
ret = ret.prefixedText
end
return bracket:format(ret)
else
return nil
end
end
-- Provides access to the luaMain function from wikitext.
function p.main(frame)
local args = require('Module:Arguments').getArgs(frame, {frameOnly = true})
return p.luaMain(args[1], args.bracket, args.fulltext) or ''
end
-- Returns true if the specified page is a redirect, and false otherwise.
function p.luaIsRedirect(page)
local titleObj = getTitle(page)
if not titleObj then
return false
end
if titleObj.isRedirect then
return true
else
return false
end
end
-- Provides access to the luaIsRedirect function from wikitext, returning 'yes'
-- if the specified page is a redirect, and the blank string otherwise.
function p.isRedirect(frame)
local args = require('Module:Arguments').getArgs(frame, {frameOnly = true})
if p.luaIsRedirect(args[1]) then
return 'yes'
else
return ''
end
end
return p
