Re: Subpages?
neither categories nor structures seem to make it possible to create pages which always have the category in the URL
Correct. Only the page's name is reflected in the URL. This allows you to recategorize a page or add it to a structure without changing the URL and breaking any incoming links.
I can't enforce a user being required to create pages in a given category
You can use the Force and limit categorization... option to require users to select from a set of categories for newly created pages. Pleasesee the docs for details.
Additionally, if you're using the Quick Edit module to create new pages, you can use the categId paramter to automatically make the newly created page be in a specific category. Please see the docs for details.
HTH,
- Rick | My Tiki Blog | My Tiki UserPage
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