Template:Ifsubst/doc

This is a documentation subpage for Template:Ifsubst.
It may contain usage information, categories and other content that is not part of the original template page.

This template is used on approximately 448,000 pages, or roughly 1154% of all pages.
To avoid major disruption and server load, any changes should be tested in the template's /sandbox or /testcases subpages, or in your own user subpage. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them.

Usage

Meta template that returns the first parameter if evaluated during substitution, and the second parameter if evaluated during transclusion.
Note that this template must be used in safesubst mode to work properly:

{{ safesubst:<noinclude/>ifsubst| yes | no }}

The |demo= parameter can be used for testing the template. Set |demo=yes to always display the yes text, |demo=no to always display the no text, or |demo={{{demo|}}} to pass through the value from the parent template.

List of subst helper templates

{{require substitution}} – Prints an error unless substituted.
- {{always substitute}} – For the doc of the above templates; prints a message asking for it be substituted.
- {{never substitute}} – The reverse of {{always substitute}}. For the doc of templates which should not be substituted; prints a message asking for it not to be substituted.
- {{may be substituted}} – For the doc of templates whose substitution is optional.
- {{substitution}} – Allows free-fill description of whether the template should be substituted and under what conditions.
{{ifsubst}} – Forks if substituted or not.
{{issubst}} – Returns "yes" if substituted.
Module:Unsubst – Prevents substitution.
Module:Unsubst-infobox – Prevents substitution for infoboxes, cleans up parameters.