Help:Parameter default
Limitation
In the case of multiple default parts, only the first applies: [a|b|c|d] is equivalent with [a|b]. The default part can only contain "|" as part of full template, parameter or link syntax within it, and within nowiki-tags. Note that "|" can be avoided in table syntax by applying HTML coding (element "<table>").
The expression for the parameter name can also contain "|", as part of full template or parameter syntax within it.
Examples, using Template:x3 containing "<noinclude>{{Please leave this line alone (template sandbox heading)}}<!--
* Welcome to the template sandbox! *
* Please leave this part alone *
* The page is cleared regularly *
* Feel free to try your editing skills below *
■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■■--></noinclude>"
and Template:t2 containing "[[w:List of people by name: {{{1}}}{{{2}}}|{{{1}}}{{{2}}}]]<noinclude>[[Category:Help:Templates templates]]</noinclude>":
- {{{a|b|c|d}}} gives b
- {{{a|{{x3|b}}}}} gives
- {{{a|{{{b|c}}}}}} gives c
- {{{a|[[b|c]]}}} gives c
- {{{{{x3|a}}|b}}} gives b - parameter aaa is undefined
- {{{{{{a|b}}}|c}}} gives c - parameter b is undefined
- {{{a|<nowiki>b|c</nowiki>}}} gives b|c - works fine for rendering text, but is not suitable for putting parameters b and c in a template call (there is no function for removing nowiki tags):
- {{t2|{{{a|<nowiki>b|c</nowiki>}}}}} gives [[w:List of people by name: b|c{{{2}}}|b|c{{{2}}}]]