yes
Detects whether the current or the given namespace has subpages enabled. Returns "yes" if it does, and an empty string otherwise.
This template can be substituted.
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{{ns has subpages}} → yes{{ns has subpages|Template}} → yes{{ns has subpages|Category}} → yes{{ns has subpages|}} (main space) →{{ns has subpages|{{ns:0}}}} (main space) →{{ns has subpages|:}} (main space) →{{ns has subpages|{{ns:Talk}}}} → yes{{ns has subpages|Category talk}} → yes{{ns has subpages|File:Foo}} →{{ns has subpages|Foo}} →{{ns has subpages|:Template}} → yes{{namespace detect}}