Template:Basepage subpage/doc
Template:Strong for Template:Terminate sentence It may contain usage information, categories and other content that is not part of the original template page. |
This is the {{When on basepage}} meta-template. It helps other templates detect if they are on a basepage (i.e. a page whose name matches the pattern "x:x") subpage ("x:x/x") or subsubpage ("x:x/x/x").
An alternative way to detect whether a page is a subpage is to combine the parser functions #ifeq:
and #titleparts
. See Alternatives for simpler text below.
Usage
badlo{{When on basepage |result if on a basepage (|result if on a subpage) (|result if on a subsubpage) (|page=pagename)}}
For example, {{Basepage|Subpage}}
on the page "User:Example" would return: Basepage
whilst on "User:Example/page" (or "User:Example/page/page", "User:Example/page/page/page", etc) it would return: Subpage
On a subsubpage such as "User:Example/page/page" (or "User:Example/page/page/page", etc), {{Basepage|Subpage|Subsubpage}}
would return: Subsubpage
Use an empty parameter to specify no action for a particular type of page. {{Basepage||Subsubpage}}
on "User:Example/page", for example, would return nothing, but would return "Subsubpage" if on "User:Example/page/page", "User:Example/page/page/page", etc (and "Basepage" if on "User:Example").
Handling equals-signs ("=")
badloUse numbered parameters if their values include equals-signs ("="), i.e.
{{1=basepage result (|2=subpage result) (|3=subsubpage result)}}
page parameter
badloThe page parameter is included for testing/demonstration. For example:
{{(basepage result)|(subpage result)|page=User:Example/test}}
Regardless of where the above is placed, it will return: (subpage result)
(because "User:Example/test" is a subpage). The page doesn't have to exist.
If page is left empty (|page=
) or undefined, the page where the template is transcluded (i.e. Template:Wikivar) is used.
page also accepts variables, e.g. {{(basepage result)|(subpage result)|page={{{page|}}} }}
Technical note
badloThis template detects subpages in all namespaces, including those without the MediaWiki subpage feature enabled.
Alternatives for simpler text
badloA subpage can be detected without using another template, by instead using the title-splitting parser function #titleparts
with #ifeq
:
{{#ifeq:{{#titleparts:{{PAGENAME}}|1|1}}|{{PAGENAME}} | [...code if on a basepage...] | [...code if on a subpage...] }}
For example, many templates can check if the page is a /sandbox version, by the similar markup with #ifeq
and #titleparts
:
- {{#ifeq: {{#titleparts:{{PAGENAME}}|1|1}} | {{PAGENAME}}
- | {{documentation}}
- | {{template sandbox notice}}
- }}
That simple logic works because Template:Template_sandbox_notice also checks the page name for "/sandbox" before displaying the sandbox notice; otherwise, any other subpage would show no extra text. By avoiding a template, and using a single #ifeq
, then the processing uses only +2 expansion depth levels, rather than +7 levels, and avoids "wp:exceeded template limits" inside a complex /doc page.
See also
badloTemplate:Namespace and pagename-detecting templates