[Templates] Recursion in macros?

[lmb]

Hi all,

now my MetaCache module is working quite nicely - links change the URL
automatically whereever I move the page, language icons can be set, the title
of the page is consistent across the entire site, "referenced by" lists show
up automatically when I add a link anywhere, I can query a list of pages which
have a particular attribute set etc.

(I'm doing this by generating a cache of the META data on each run of ttree,
even though this requires two runs to fully update all sites as I am
generating purely static result pages - if I would dynamically generate them
I'd just need to check them in, but that's not what I want ;-)

And I am wondering how to best generate the navigation completely
automatically. This amounts to a tree traversal; the obvious way to do this
would be a recursive macro ;-)

But I doubt that MACROs are recursion safe, are they?

The other option would be to do this in a Perl function (much cleaner,
likely); but then I'd need to evaluate a template block in my function
(because I don't want to have all the HTML hardcoded, obviously); how do I do
this?

I'd imagine the call would look something like this:

[% BuildNav(...) BLOCK %]
... nav template
[% END %]

An even _further_ option would be to have the Perl function return a specially
formatted data structure which I could traverse with a FOREACH loop and where
each step contained information of whether to go up a level (ie, close a
</UL>) or go down one further (start a new <UL>).

Any thoughts on this?

Oh, and while I'm at it, I saw a recent discussion on Image modules; does
anyone have a nice module for generating image galleries etc?


Sincerely,
	Lars


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