<one metric ton of useful stuff, in various messages, all of which I agree with>
Including...
The data binding folks have tried to address the problem using XML Schema, and the result is, hmmm, "unpleasant" to use something polite. The SOAP and WSDL people have been at it, and I won't even describe the result because I couldn't possibly be polite about it.<snip>
Imho a grammar-based approach would likely be too low-level. I'm currently betting on something that would mix XBind[1] and Regular Fragmentations[2]. The first one defines simple mappings as described above, the second tells you how to parse data in XML documents that has structure not expressed in XML (eg <date>2003-03-26</date>) so that it is seen in a structured way, without the need for typing.
One very cool thing that could be done in Perl 6 would be to take an XBind+RegFrag document and generate a grammar derived from the P6 XML grammar that would 1) be specific to the vocabulary (and thus hopefully faster than a generic XML grammar, though I don't have /too/ much hope) and 2) directly produce the object representation you want and return it in the parse object.
Indeed. This is the primary problem space. Nobody has done this well. If we could provide a toolset for doing this, we would Really Have Something.
My initial query about the ambiguously-named "P6ML" was not based so much on a notion that such an effort couldn't be done in Perl5, and more on the notion that it may be far _more_ possible to do this, quickly & credibly, using P6 typing/OO and the new regex engine. As I said, I've done quite a bit of prototyping, and the P5 solutions can be very, very tedious. (P5 and P6 may be mostly alike, but it's the parts that aren't "mostly" that have driven the very need for P6 -- and just so happen to be the very parts that make this problem so awkward in P5.)
And in case I haven't mentioned it this week, you Parrot folks are my heros.
[0]http://use.perl.org/~gnat/journal/11081 [1]http://www.prescod.net/xml/xbind/ [2]http://www.simonstl.com/projects/fragment/
Thanks for those... I was aware of the first two links, but I had completely missed the Frag one -- I plead ignorance on that. You are correct, it looks quite promising.
MikeL
