Module:Unsubst
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Helper module to facilitate a substituted template transform into a template transclusion.
Maintenance templates, such as {{Citation needed}} or {{Refimprove}}, should never be substituted. A trick to avoid that is to make a template substitute to its transcluded form.
Usage
To turn a template into a self-substituting template, wrap the existing template code with:
{{ {{{|safesubst:}}}#invoke:Unsubst||$B=
[ ... existing template code ... ]
}}
The wikitext to display when not substed must be given as "$B". A parameter "$N" may also be seen in some templates; this was required in an older version of the module, but is no longer necessary and may be removed. Such templates are automatically placed in Category:Calls to Module:Unsubst that use $N.
All other parameters passed to the #invoke will be copied to the generated template invocation as default values. If the value of any of these default parameters is "__DATE__", that value in the generated template invocation will be the current month and year.
Some templates have a <noinclude> but no matching </noinclude> at the end of the template. In such cases the missing </noinclude> must be added before the ending }}.
Example
Consider a template Template:Example containing the following code:
{{ {{{|safesubst:}}}#invoke:Unsubst||foo=bar |date=__DATE__ |$B=
[ ... Template code goes here ... ]
}}
| Original | Result |
|---|---|
| {{subst:example}} | {{Example|foo=bar|date=December 2024}} |
| {{subst:example|foo=X}} | {{Example|foo=X|date=December 2024}} |
| {{subst:example|baz=X}} | {{Example|foo=bar|baz=X|date=December 2024}} |
| {{subst:example|date=January 2001}} | {{Example|foo=bar|date=January 2001}} |
local checkType = require('libraryUtil').checkType
local p = {}
local BODY_PARAM = '$B'
local specialParams = {
['$params'] = 'parameter list',
['$aliases'] = 'parameter aliases',
['$flags'] = 'flags',
['$B'] = 'template content'
}
function p.main(frame, body)
-- If we are substing, this function returns a template invocation, and if
-- not, it returns the template body. The template body can be specified in
-- the body parameter, or in the template parameter defined in the
-- BODY_PARAM variable. This function can be called from Lua or from
-- #invoke.
-- Return the template body if we aren't substing.
if not mw.isSubsting() then
if body ~= nil then
return body
elseif frame.args[BODY_PARAM] ~= nil then
return frame.args[BODY_PARAM]
else
error(string.format(
"no template content specified (use parameter '%s' from #invoke)",
BODY_PARAM
), 2)
end
end
-- Sanity check for the frame object.
if type(frame) ~= 'table'
or type(frame.getParent) ~= 'function'
or not frame:getParent()
then
error(
"argument #1 to 'main' must be a frame object with a parent " ..
"frame available",
2
)
end
-- Find the invocation name.
local mTemplateInvocation = require('Module:Template invocation')
local name = mTemplateInvocation.name(frame:getParent():getTitle())
-- Combine passed args with passed defaults
local args = {}
if string.find( ','..(frame.args['$flags'] or '')..',', ',%s*override%s*,' ) then
for k, v in pairs( frame:getParent().args ) do
args[k] = v
end
for k, v in pairs( frame.args ) do
if not specialParams[k] then
if v == '__DATE__' then
v = mw.getContentLanguage():formatDate( 'F Y' )
end
args[k] = v
end
end
else
for k, v in pairs( frame.args ) do
if not specialParams[k] then
if v == '__DATE__' then
v = mw.getContentLanguage():formatDate( 'F Y' )
end
args[k] = v
end
end
for k, v in pairs( frame:getParent().args ) do
args[k] = v
end
end
-- Trim parameters, if not specified otherwise
if not string.find( ','..(frame.args['$flags'] or '')..',', ',%s*keep%-whitespace%s*,' ) then
for k, v in pairs( args ) do args[k] = mw.ustring.match(v, '^%s*(.*)%s*$') or '' end
end
-- Pull information from parameter aliases
local aliases = {}
if frame.args['$aliases'] then
local list = mw.text.split( frame.args['$aliases'], '%s*,%s*' )
for k, v in ipairs( list ) do
local tmp = mw.text.split( v, '%s*>%s*' )
aliases[tonumber(mw.ustring.match(tmp[1], '^[1-9][0-9]*$')) or tmp[1]] = ((tonumber(mw.ustring.match(tmp[2], '^[1-9][0-9]*$'))) or tmp[2])
end
end
for k, v in pairs( aliases ) do
if args[k] and ( not args[v] or args[v] == '' ) then
args[v] = args[k]
end
args[k] = nil
end
-- Remove empty parameters, if specified
if string.find( ','..(frame.args['$flags'] or '')..',', ',%s*remove%-empty%s*,' ) then
local tmp = 0
for k, v in ipairs( args ) do
if v ~= '' or ( args[k+1] and args[k+1] ~= '' ) or ( args[k+2] and args[k+2] ~= '' ) then
tmp = k
else
break
end
end
for k, v in pairs( args ) do
if v == '' then
if not (type(k) == 'number' and k < tmp) then args[k] = nil end
end
end
end
-- Order parameters
if frame.args['$params'] then
local params, tmp = mw.text.split( frame.args['$params'], '%s*,%s*' ), {}
for k, v in ipairs(params) do
v = tonumber(mw.ustring.match(v, '^[1-9][0-9]*$')) or v
if args[v] then tmp[v], args[v] = args[v], nil end
end
for k, v in pairs(args) do tmp[k], args[k] = args[k], nil end
args = tmp
end
return mTemplateInvocation.invocation(name, args)
end
p[''] = p.main -- For backwards compatibility
return p
