Right, but DTML code is not valid XML code. It can't be edited in an XML editor, stored in an XML repository, routed through XML-based workflow, etc. etc.

But using DTML you can generate any kind of XML that you want, and get the level of effectiveness that you are stating. And then that generated XML can be routed through all the XML based workflow that you want. I've done a couple of relatively small experiments with this, once using DTML over a sequence of Tabula records to generate a good size XML file to test an XML parser. So it was an XML expression of objects in the database, but using DTML allowed me to make the XML structure that I wanted independant of the structure of the Zope database or the Tabula database or what-have-you. And even that doesn't stop you from using XSL directly in Zope. On NT *twitch* with IE5 *twitch* you could make a Zope object to call Microsofts XSL processor. Then you could have a DTML page that goes over some sort of query to return an XML document linked to the XSL style sheet. Add another document that calls the XSL processor and passes in the rendered XML document, and Walla!

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I would suggest that Zope should use XSL template syntax for DTML templates as far as is possible.

It appears to me that DTML and XSL represent two very different approaches to solving the same or similar problems. They are both intended for generating text from objects. DTML generates text from Python objects. XSL generates text from XML objects.

Not quite. XSL generates XML objects (technically speaking, "nodes") from other XML objects (other nodes).

Using XML to go through XML and generate XML? :)

The big difference, of course, is that XSL's set of expressions is quite limited where as Python is quite flexible. That's why I propose using the same syntax but changing the expressions to be Python expressions.

Doesn't this kill off any sort of 'XSL portability'? I can imagine a system where both Zope and, say, Access *twitch* (independantly of Zope) could generate XML documents of the same or similar DTD and have the same XSL document(s) be able to render them both on an entirely different machine.

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Given the very different natures of DTML and XSL, I don't see much point in making the syntaxes all that consistent.

Do you have another XML-compliant syntax in mind or have you decided that XML compliance isn't critical?

It's easy to write some DTML to generate XML. There's a big piece of compliance right there. Currently, there's no XML on the intake side. I think this is a _far_ more important thing to do than spend a bunch of time writing yet another XSL parser. I would rather be able to generate that phone book file as XML and be able to upload it into Zope as intelligent-ish Zope objects (into a Tabula, as Zope Folders, or who-knows-what) and write a simple <!--#in "phone_numbers(zip=22401)"--> <TR> <TD><!--#var fullname--></TD><TD><!--#var phone--></TD> </TR> <!--#/in--> DTML document rather than the complex XSL involved. Then I can add the ability for people to add new phone numbers and modify their entries in this dataset and re-export it to a new updated XML file, and use some other XSL parser to generate a printable phone book, PDF, RTF, and HTML from that. The XML file can be easily done in DTML by: <?xml version="1.0"> <phonebook zip="<!--#var inZip-->"> <!--#in "phone_numbers(zip=inZip)"--> <listing for="<!--#var fullname-->"> <fullname><!--#var fullname--></fullname> <phone><!--#var phone--> </listing> <!--#/in--> </phonebook>

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It may very well. If Zope made it easy to generate XML from Zope (ie Python) objects, then people who like XSL could apply XSL transformations to the resulting XSL, bypassing DTML altogether.

Sure, but how do I specify the objects that I want to work on from the XSL stylesheet? You can't [*] export the database as a single XML document, so you must allow a syntax that allows drilling into Python objects: Python syntax.

See above. There's a few variations that can be done.

I don't really see the difference. Either an extended XSL replaces DTML or an XSL-syntax DTML replaces DTML. All I'm saying is that the next generation templating syntax should be XSL-based.

XSL is _much much much_ tougher for beginners to Grok. It's very very powerful, yes, but sometimes just to do a simple tabular based report in it is waaaay too much of a headache. We discussed this a long time ago here at digicool with just an XML based replacement for DTML (XSL was just barely off the drawing board at the time of these discussions). I still emphasize that it's (a) not that hard to generate complient XML using DTML (the DTML document itself doesn't have to be XML complient, just the document as rendered), and (b) importing XML should be a bigger priority. just my <CURRENCY STYLE="cents">.02</CURRENCY>.