![](https://upload.wikimedia.org/wikipedia/commons/thumb/4/43/Test_Template_Info-Icon_-_Version_%282%29.svg/50px-Test_Template_Info-Icon_-_Version_%282%29.svg.png)
This module, migrated from origins in Module:Hatnote, provides functionality for formatting links for display, including that powering the {{format link}} template.
It can pretty-format section links with the section symbol ("§") and appropriate whitespace, it automatically escapes category and file names with the colon trick, and includes functionality for italicizing the page or section name, and for detecting and categorizing results that produce red links.
Use from wikitext
The functions in this module cannot be used directly from #invoke, and must be used through templates instead. Please see Template:Format link for documentation on usage of that template.
Use from other Lua modules
To load this module from another Lua module, use the following code:
local mFormatLink = require('Module:Format link')
You can then use the functions as documented below.
_formatLink
mFormatLink._formatLink{
link = 'Link',
display = 'Display',
target = 'Target',
italicizePage = true,
italicizeSection = true,
categorizeMissing = 'Pages using formatted red links'
}
Formats link as a wikilink. Categories and files are automatically escaped with the colon trick, and links to sections are automatically formatted as page § section, rather than the MediaWiki default of page#section.
Several options modify the output:
- If the display value is present, then it will be used as a display value. Any manual piping (using the
{{!}}
magic word or similar) present in link will be overridden by the display value if present. - If the target value is present, then it will override link as a target, but the result will still be displayed using either the value from display, or the result of formatting link.
- If italicizePage is true, then the page portion of the link is italicized if present.
- If italicizeSection is true, then the section portion of the link is italicized if present.
- If categorizeMissing is a non-empty string, then that value is used as a category name, and that category will be applied if the resulting target of the link (no matter whether through link or through target) doesn't exist.
- Examples
mFormatLink._formatLink{link = 'Foo#Bar'}
→ [[:Foo#Bar|Foo § Bar]] → Foo § BarmFormatLink._formatLink{link = 'Baz', display = 'Qux'}
→ [[:Baz|Qux]] → QuxmFormatLink._formatLink{link = 'Foo|Bar', display = 'Baz'}
→ [[:Foo|Baz]] → BazmFormatLink._formatLink{link = '#Foo', target = 'Example#Foo'}
→ [[:Example#Foo|§ Foo]] → § FoomFormatLink._formatLink{link = 'The Lord of the Rings#Plot', italicizePage = true}
→ [[:The Lord of the Rings#Plot|''The Lord of the Rings'' § Plot]] → The Lord of the Rings § PlotmFormatLink._formatLink{link = 'Cybercrime Prevention Act of 2012#Disini v. Secretary of Justice', italicizeSection = true}
→ [[:Cybercrime Prevention Act of 2012#Disini v. Secretary of Justice|Cybercrime Prevention Act of 2012 § ''Disini v. Secretary of Justice'']] → Cybercrime Prevention Act of 2012 § Disini v. Secretary of JusticemFormatLink._formatLink{link = 'Nonexistent page', categorizeMissing = 'Example'}
→ [[:Nonexistent page]][[Category:Example]] → Nonexistent pagemFormatLink._formatLink{link = 'Existing', categorizeMissing = 'Example'}
→ [[:Existing]] → Existing
formatPages
mFormatLink.formatPages(options, pages)
This derived function is useful for lists that format many links. It formats an array of pages using the _formatLink function, and returns the result as an array. Options in the options table are applied, and use the same names as the options for _formatLink.
- Example
mFormatLink.formatPages({categorizeMissing = 'Example'}, {'Foo#Bar', 'Nonexistent page'})
→{'[[:Foo#Bar|Foo § Bar]]', '[[:Nonexistent page]][[Category:Example]]'}
Errors
If _formatLink is used and neither a link nor a target argument is provided, then the module will produce an error message instead of its usual output, as it cannot then produce valid output.
You can solve this error by providing appropriate parameters to _formatLink, or you may want to ensure that a more descriptive error is provided by a downstream template or module when it would otherwise call _formatLink with inadequate arguments.
--------------------------------------------------------------------------------
-- Format link
--
-- Makes a wikilink from the given link and display values. Links are escaped
-- with colons if necessary, and links to sections are detected and displayed
-- with " § " as a separator rather than the standard MediaWiki "#". Used in
-- the {{format link}} template.
--------------------------------------------------------------------------------
local libraryUtil = require('libraryUtil')
local checkType = libraryUtil.checkType
local checkTypeForNamedArg = libraryUtil.checkTypeForNamedArg
local mArguments -- lazily initialise [[Module:Arguments]]
local mError -- lazily initialise [[Module:Error]]
local yesno -- lazily initialise [[Module:Yesno]]
local p = {}
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-- Helper functions
--------------------------------------------------------------------------------
local function getArgs(frame)
-- Fetches the arguments from the parent frame. Whitespace is trimmed and
-- blanks are removed.
mArguments = require('Module:Arguments')
return mArguments.getArgs(frame, {parentOnly = true})
end
local function removeInitialColon(s)
-- Removes the initial colon from a string, if present.
return s:match('^:?(.*)')
end
local function maybeItalicize(s, shouldItalicize)
-- Italicize s if s is a string and the shouldItalicize parameter is true.
if s and shouldItalicize then
return '<i>' .. s .. '</i>'
else
return s
end
end
local function parseLink(link)
-- Parse a link and return a table with the link's components.
-- These components are:
-- - link: the link, stripped of any initial colon (always present)
-- - page: the page name (always present)
-- - section: the page name (may be nil)
-- - display: the display text, if manually entered after a pipe (may be nil)
link = removeInitialColon(link)
-- Find whether a faux display value has been added with the {{!}} magic
-- word.
local prePipe, display = link:match('^(.-)|(.*)$')
link = prePipe or link
-- Find the page, if it exists.
-- For links like [[#Bar]], the page will be nil.
local preHash, postHash = link:match('^(.-)#(.*)$')
local page
if not preHash then
-- We have a link like [[Foo]].
page = link
elseif preHash ~= '' then
-- We have a link like [[Foo#Bar]].
page = preHash
end
-- Find the section, if it exists.
local section
if postHash and postHash ~= '' then
section = postHash
end
return {
link = link,
page = page,
section = section,
display = display,
}
end
local function formatDisplay(parsed, options)
-- Formats a display string based on a parsed link table (matching the
-- output of parseLink) and an options table (matching the input options for
-- _formatLink).
local page = maybeItalicize(parsed.page, options.italicizePage)
local section = maybeItalicize(parsed.section, options.italicizeSection)
if (not section) then
return page
elseif (not page) then
return mw.ustring.format('§ %s', section)
else
return mw.ustring.format('%s § %s', page, section)
end
end
local function missingArgError(target)
mError = require('Module:Error')
return mError.error{message =
'Error: no link or target specified! ([[' .. target .. '#Errors|help]])'
}
end
--------------------------------------------------------------------------------
-- Main functions
--------------------------------------------------------------------------------
function p.formatLink(frame)
-- The formatLink export function, for use in templates.
yesno = require('Module:Yesno')
local args = getArgs(frame)
local link = args[1] or args.link
local target = args[3] or args.target
if not (link or target) then
return missingArgError('Template:Format link')
end
return p._formatLink{
link = link,
display = args[2] or args.display,
target = target,
italicizePage = yesno(args.italicizepage),
italicizeSection = yesno(args.italicizesection),
categorizeMissing = args.categorizemissing
}
end
function p._formatLink(options)
-- The formatLink export function, for use in modules.
checkType('_formatLink', 1, options, 'table')
local function check(key, expectedType) --for brevity
checkTypeForNamedArg(
'_formatLink', key, options[key], expectedType or 'string', true
)
end
check('link')
check('display')
check('target')
check('italicizePage', 'boolean')
check('italicizeSection', 'boolean')
check('categorizeMissing')
-- Normalize link and target and check that at least one is present
if options.link == '' then options.link = nil end
if options.target == '' then options.target = nil end
if not (options.link or options.target) then
return missingArgError('Module:Format link')
end
local parsed = parseLink(options.link)
local display = options.display or parsed.display
local catMissing = options.categorizeMissing
local category = ''
-- Find the display text
if not display then display = formatDisplay(parsed, options) end
-- Handle the target option if present
if options.target then
local parsedTarget = parseLink(options.target)
parsed.link = parsedTarget.link
parsed.page = parsedTarget.page
end
-- Test if page exists if a diagnostic category is specified
if catMissing and (mw.ustring.len(catMissing) > 0) then
local title = nil
if parsed.page then title = mw.title.new(parsed.page) end
if title and (not title.isExternal) then
local success, exists = pcall(function() return title.exists end)
if success and not exists then
category = mw.ustring.format('[[Category:%s]]', catMissing)
end
end
end
-- Format the result as a link
if parsed.link == display then
return mw.ustring.format('[[:%s]]%s', parsed.link, category)
else
return mw.ustring.format('[[:%s|%s]]%s', parsed.link, display, category)
end
end
--------------------------------------------------------------------------------
-- Derived convenience functions
--------------------------------------------------------------------------------
function p.formatPages(options, pages)
-- Formats an array of pages using formatLink and the given options table,
-- and returns it as an array. Nil values are not allowed.
local ret = {}
for i, page in ipairs(pages) do
ret[i] = p._formatLink{
link = page,
categorizeMissing = options.categorizeMissing,
italicizePage = options.italicizePage,
italicizeSection = options.italicizeSection
}
end
return ret
end
return p