Re: XML Conformance Levels [Was: ERB Decisions of March 26th]
In message <199703270933.JAA25814@curia.ucc.ie> Peter Flynn writes:
> > > O goddess, please not. This is in jest, right?
> Murray writes:
> > Nope. But what's the alternative?
> > XML-CORE: fully supported or no support at all
> > XML-LINK: fully supported or no support at all
> > XML-STYLE: fully supported or no support at all
> > Now really sit back and let that sink in a minute. If you want to develop
> > an XML processor/application, you either support CORE or not. Fine so far.
> > But if you want *any* linking or stylesheets (and you can't approach HTML's
> > functionality at all without both) then you must implement both *completely*.
I don't see this follows necessarily. I do not - at this stage - intend to
implement stylesheets at all, but I do intend (within my technical limitations
and an unknown final draft) to implement LINK completely. I have implemented
TEI though I will have to extend it (if not in XML, then at application
level). [I need to be able to search numbers, chemical formulae, etc. after
retrieving 'resources' via TEI.] I am working on what I believe to be a
'link processor' for JUMBO, though I'm not yet clear precisely what the spec
The reality with JUMBO is that I want to
(a) implement XML-CORE completely. The only sensible way is via NXP/Lark.
(a1) implement some application functionality (e.g. editing, browsing,
rendering, etc.) on top of XML-CORE. We all agree that that is my business -
if it's reusable by other members of the community, great.
(b) I want to have the whole of XML-LINK. Whether I do depends on whether
- I am capable of doing it all in Java
- someone else writes reusable components for TEI and/or LINK
(b1) I want the client-side application to be able to search documents/objects.
I choose to use TEI for that because:
- I understand it (unlike DSSSL)
- it does (most of) what I want.
- it might come for free as a reusable component
- it will have wide currency.
I will, at least, have to have an application-specific method for extending
the TEI addressing. FOREIGN seemed obvious and very cheap, but I've had my say.
(b2) I want to implement robust hyperlinking. I will use XML-LINK (I am
taking it on trust that the ERB knows better than I do what I need :-).
The latest draft about Xptr is precisely what I want, for example.)
However, I may fail in my ability to implement links, and my application
will simply say to the user "sorry, JUMBO is not clever enough to support
this feature". I suspect we are going to see a good deal of that :-)
(c) I have no obvious need for DSSSL. There are several reasons:
- it will take me 2-3 months to understand it and see if Kawa or
similar is useful to me. (Scheme is a non-starter, sorry)
- our community will take years to write in it.
- they think that plugins and CSS will solve their problems anyway
- it offers no functionality *after* parsing (or at least after
rendering) as far as I can see.
(c1) I believe we can solve our 'style' problems by supplying methods attached
to elements/objects. I may well be wrong, but it works so far. For example,
I have taken Jon's PLAY and hacked a very few classes which render it
appropriate styles. Thus there is a PERSONA class which draws a little icon
and changes the font. Where appropriate it uses TEI notation to identify
components to process. I doubt there is much more code than DSSSL equivalent.
The key question which I hope XML-WG/ERB will answer is "how do I specify
whcih version of a class to apply to FOO?" That seems to me to be isomorphic
with "which style sheet containing FOO shall I use?" and *possibly* "how do
I get it" :-).
It is possible that this question will be answered under XML-LINK rather than
XML-STYLE since it could be thought of as 'behaviour'. If so, great! :-)
Peter Murray-Rust, domestic net connection
Virtual School of Molecular Sciences