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=November 2024}} |
{{subst:example|foo=X}} | {{Example|foo=X|date=November 2024}} |
{{subst:example|baz=X}} | {{Example|foo=bar|baz=X|date=November 2024}} |
{{subst:example|date=January 2001}} | {{Example|foo=bar|date=January 2001}} |
local p = {} local specialParams = { ['$N'] = 'template name', -- Deprecated, but keeping until it is removed from transcluding templates ['$B'] = 'template content', } p[''] = function ( frame ) if not frame:getParent() then error( '{{#invoke:Unsubst|}} makes no sense without a parent frame' ) end if not frame.args['$B'] then error( '{{#invoke:Unsubst|}} requires parameter $B (template content)' ) end if mw.isSubsting() then ---- substing -- Combine passed args with passed defaults local args = {} for k, v in pairs( frame.args ) do if not specialParams[k] then if v == '__DATE__' then v = mw.getContentLanguage():formatDate( 'F Y' ) end args[k] = v end end for k, v in pairs( frame:getParent().args ) do args[k] = v end -- Build an equivalent template invocation -- First, find the title to use local titleobj = mw.title.new(frame:getParent():getTitle()) local title if titleobj.namespace == 10 then -- NS_TEMPLATE title = titleobj.text elseif titleobj.namespace == 0 then -- NS_MAIN title = ':' .. titleobj.text else title = titleobj.prefixedText end -- Build the invocation body with numbered args first, then named local ret = '{{' .. title for k, v in ipairs( args ) do if string.find( v, '=', 1, true ) then -- likely something like 1=foo=bar, we need to do it as a named arg break end ret = ret .. '|' .. v args[k] = nil end for k, v in pairs( args ) do ret = ret .. '|' .. k .. '=' .. v end return ret .. '}}' else ---- Not substing -- Just return the "body" return frame.args['$B'] .. (frame.args['$N'] and frame:getParent():getTitle() == mw.title.getCurrentTitle().prefixedText and '[[Category:Calls to Module:Unsubst that use $N]]' or '') end end return p