Template:Ifnotempty: Difference between revisions

Template page
m (Changed protection level for "Template:Ifnotempty": high-risk template with 4000+ transclusions ([Edit=Require template editor access] (indefinite) [Move=Require template editor access] (indefinite)))
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<includeonly>{{ {{{|safesubst:}}}{{ {{{|safesubst:}}}#if:{{{1}}}|p1|p2}}|{{{2}}}|{{{3|}}}}}</includeonly><noinclude>
<includeonly>{{ {{{|safesubst:}}}{{ {{{|safesubst:}}}#if:{{{1}}}|p1|p2}}|{{{2}}}|{{{3|}}}}}</includeonly><noinclude>{{Documentation}}
 
{{Documentation|content=
 
With this template [[mw:Help:Extension:ParserFunctions|#if]] can be used in a way such that it does not [[m:Help:Newlines_and_spaces#Stripping_on_expansion|strip spaces and newlines]] from the "then" and "else" part. For evaluating the condition spaces and newlines are stripped like with ParserFunctions.
 
This template can be substituted.
 
==Usage==
*<code><nowiki>{{ifnotempty| x | A | B }}</nowiki></code> gives "{{ifnotempty| x | A | B }}"
*<code><nowiki>{{ifnotempty|x| A | B }}</nowiki></code> gives "{{ifnotempty|x| A | B }}"
*<code><nowiki>{{ifnotempty| | A | B }}</nowiki></code> gives "{{ifnotempty| | A | B }}"
*<code><nowiki>{{ifnotempty|| A | B }}</nowiki></code> gives "{{ifnotempty|| A | B }}"
Compare:
*<code><nowiki>{{#if:x| A | B }}</nowiki></code> gives "{{#if:x| A | B }}"
*<code><nowiki>{{#if:| A | B }}</nowiki></code> gives "{{#if:| A | B }}"
 
==Internal technical details==
For evaluating the condition (determining non-emptiness of the first parameter) the template uses parser function #if, producing 1 if the condition is true, and 2 otherwise. The template with name equal to "P" followed by the index value produced (hence [[Template:P1]] or [[Template:P2]]), is called with as parameters A and B. This produces either A or B, without trimming.
 
==See also==
*[[Template:If]]
*[[m:Template:Ifnotempty]]
 
[[Category:If-then-else templates]]
 
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Revision as of 19:12, 14 December 2021