“Multi-Rule XUL Templates: Not Documented”

One important point I failed to include in last night's post about XUL templates: the problem I finally figured out is not documented anywhere, as far as I can see. XUL template documentation is generally found online in a few different places: mozilla.org, XUL Planet, and online copies of the book, "Creating Application with Mozilla." Offline, my preferred resource is Rapid Application Development with Mozilla.

None of them mention that secondary template rules must use the same variable names as the first rule (though all of the examples work that way, nothing indicated that was a requirement). I have discovered one other place this is mentioned, though: in a single sentence in a reply to a comment at the bottom of one page on XUL Planet.

In fact, you are required to use the same container variable (the one defined on the content tag) and the same member variable (defined in the uri in the action) in all rules, although they don't need to point to the same kind of data - Neil