Where is there an end of it? | Alex Brown's weblog

De Gustibus

Sarah has persuaded me to submit an entry for the The normblog Posterity Collection poll. It is:

1. Poet - Chaucer
2. Playwright - Shakespeare
3. Novelist - E.M. Forster
4. Composer - Beethoven, Bruckner, Mozart, Schubert
5. Jazz musician - Milt Jackson
6. Rock or pop star/group - ABBA
7. Country music ditto
8. Movie director - Michael Powell
9. Painter - Vermeer
10. Photographer
11. Sculptor - Richard Serra
12. Architect

E.M. Forster - really? Strange what this exercise makes you discover about yourself ...

(Actually, I'm distracted by the fact there is no Unicode character for the backwards B in ABBA).

SC 34 Meetings, Prague - Day 1


SC 34 have a week of meetings in Prague. Today only WG 1 was meeting and I – for the first time – was convening it; an honour, and a slightly daunting one at that.

It was, though, very reassuring to feel that, for the first time since the OOXML days, things were returning to normal, and that the structural changes SC 34 has put in place has allowed WG 1 to return to its true purpose for XML infrastructure technologies: principally schema languages.

It was also great to see wide International participation, with experts in attendance from Canada, China, The Czech Republic, France, Japan, South Africa the United Kingdom.

We had a full agenda and the meeting day varied from some in-the-trenches technical work (prinipally on 19757-8 - DSRL) to some more strategic topics. A couple of these are worth a special mention.

XML 1.0 Fifth Edition

The first is the issue of what to do about XML 1.0 Fifth Edition. The particular revision has caused consternation in some parts of the XML community, by breaking compatibility with earlier versions of XML. XML titans such as Tim Bray, James Clark and David Carlisle have lined up to condemn the move, and Elliotte Rusty Harold has gone so far as to write that "The W3C Core Working group has broken faith with the XML community", and that,

Perhaps the time has come to say that the W3C has outlived its usefulness. Really, has there been any important W3C spec in this millennium that's worth the paper it isn't printed on? [...] I think we might all be better off if the W3C had declared victory and closed up shop in 2001.

Which, if nothing else, shows that when standards get passed which people don't like, the poor standards bodies get it in the neck — a phenomenon regular readers of this blog will have come across before.

So, the practical question is: what do we do about this in SC 34? If we have some Standards which refer to the Fifth edition, and others which refer to earlier editions, then there is a danger those standards are not interoperable, which flies in the face of JTC 1 requirements.

The initial mood around the table seemed to be that politics could be avoided by adopting an approach of "user beware". We would allow standards to mix references to the different versions and if implementations blew up on users then they'd know who to blame: the W3C.

On further reflection, however, consensus seems to be homing in on the idea that it would be better to keep all of our references pointing to XML 1.0 Fourth Edition for now, and to wait until the XML technologies around the Fifth edition matured (W3C has some work to do making XML 5Ed compatibile with other W3C technologies). Then we (and thus users) would be able to embrace 5Ed more enthusiastically; for amid the turmoil it does provide some features (such as a bigger repertoire of name characters) that are wanted by some of our non-Western users.

Schema Copyright

Another interesting issue surrounded schema copyright. When a user downloads a free ISO or IEC standard from ITTF's list, they are bound by a EULA which, inter alia, stipulates:

Under no circumstances may the electronic file you are licensing be copied, transferred, or placed on a network of any sort without the authorization of the copyright owner.

Now this raises a number of questions, but the immediate one facing WG 1 is the issue of schemas. When a standard contains a schema, it is perfectly reasonable for a user to want to extract that and use it for validation – which in most scenarios definitely will require it to be "transferred, or placed on a network".

Following an exchange with Geneva it became apparent that what we should be doing is to include a separate license with the schema, which derogates from the EULA to grant the necessary permissions. Geneva suggested a BSD-esque licence but suggested SC 34 should sensibly innovate around it:

The following permission notice and disclaimer shall be included in all copies of this XML schema ("the Schema"), and derivations of the Schema:
Permission is hereby granted, free of charge in perpetuity, to any person obtaining a copy of the Schema, to use, copy, modify, merge and distribute free of charge, copies of the Schema for the purposes of developing, implementing, installing and using software based on the Schema, and to permit persons to whom the Schema is furnished to do so, subject to the following conditions:
In addition, any modified copy of the Schema shall include the following


Already the experts are starting to hack this around and one well-supported thought was to have it submitted to the OSI to ensure it was compatible with any conceivable FOSS scenario. If any reader has expertise in this area, I'd be very interested to hear from them...

XML Prague 2009, Day 2


I'm afraid I missed the opening 3 talks of the day, as I was too busy fretfully primping my slides in readiness for my talk (directly after the coffee break). Luckily I will be able to catch up with the video later.

Following my talk, Mark Howe and Tony Graham presented on Xcruciate. The audience was very taken with Mark's opening cartoons (do check them out). I'm still not entirely sure I'm grokking what an XML-server actually is. Seems to be a bunch of XML functionality that's remotely invocable ... It's C-based, and there looks to be some interesting stuff under the hood ...

After lunch, Petr Nálevk's topic was "Advanced Automated Authoring with XML. Petr demonstrated an array of snazzy looking documentation generated with a variety of wizardly XML toolchains. Just as notable as these were the snazzy effects on display from his use of an Ubuntu desktop!

Next up, it's Václav Trojan to talk about XDefinition 2.1. This turns out to be a kind of validation language. Václav claims it can operate on data sets of "unlimited size" - and it also appears to allow transformations and miscellaneous XML programming. The strength appears to be its interface with non XML data external to documents - something the current standards are quite weak on. However, the phantasmagoria of functionality on offer seems tobe controlled by a proprietary language stored in attributes - I'm pretty sure I wouldn't start from here.

To round proceedings off, it fell to the effervescent Robin Berjon to give a tour of developments in the SVG space. As promised, his presentation delivered several delightful visual bon bons and proved the perfect end to a great conference!

Robin Berjon
Robin Berjon

XML Prague 2009, Day 1

Night Falls on Old Prague

I am in Prague for the XML Prague conference, and for a week of meetings of ISO/IEC JTC 1 SC 34. Here is a running report of day 1 of the conference ...

Day 1 kicked off, after a welcome from Mohamed Zergaoui, with a presentation from Mike Kay (zOMG - no beard!) on the state of XML Schema 1.1. Mike gave a lucid tour of XML Schema's acknowledged faults, but maintained these must not distract us too much from the technology's industrial usefulness. XML Schema 1.1 looks to me mostly like a modest revamp: some tidying and clarification under the hood. One notable new feature is however to be introduced: assertions - a cut down version of the construct made popular by Schematron. Mike drew something of collective intake of breath when he claimed it was to XML Schema 1.1's advantage that it was incorprating multiple kinds of validation, and that it was "ludicrous" to validate using multiple schema technologies.

A counterpoint to this view came in the next presentation from MURATA Makoto. Murata-san demonstrated the use of NVDL to validate Atom feed which contain extension, claiming NVDL was the only technology that allows this to be done without manually re-editing the core schemas every time a new extension is used.

After coffee, Ken Holman presented on "code lists" - a sort of cinderalla topic within XML validation but an important one, as code lists play a vital role in document validity in most real world XML documents of any substance. Ken outlined a thorough mechanism for validation of documents using code lists based on Genericode and Schematron.

Before Lunch,  Tony Graham took a look at "Testing XSLT" and gave an interesting tour of some of the key technologies in this space. One of his key conclusions, and one which certainly struck a chord with me, was the assertion that ultimately the services of our own eyes are necessary for a complete test to have taken place

Continuing the theme, Jeni Tennison introduced a new XSLT testing framework of her invention: XSpec. I sort of hope I will never have to write substantial XSLTs which merit testing, but if I do then Jeni's framework certainly looks like TDB for TDD!

Next, Priscilla Walmsley took the podium to talk about FunctX a useful-looking general-purpose library of XPath 2.0 (and therefore XQuery) function. Priscilla's talk nicely helped to confirm a theme that has been emerging today, of getting real stuff done. This is not to say there is not a certain geeky intellectualism in the air - but: it's to a purpose.

After tea, Robin Berjon gave an amusing tour of certain XML antipatterns. Maybe because his views largely coincided with mine I thought it a presentation of great taste and insight. Largely, but not entirely :-)

Next up, Ari Nordström gave a presentation on "Practical Reuse in XML". His talk was notable for promoting XLink, which had been a target of Robin Berjon's scorn in the previous session (though now without some contrary views from the floor). Also URNs were proposed as an underpinning for identification purposes - a proposal which drew some protests from the ambient digiverse

To round off the day's proceedings, George Cristian Bina gave a demo of some upcoming features in the next version of the excellent oXygen XML Editor. This is software I am very familiar with, as I use it almost daily for my XML work. George's demo concentrated on the recent authoring mode for oXygen, which allows creation of markup in a more user-friendly wordprocessor-like environment. I've sort of used this on occasion, and sort of felt I've enjoyed it at the time. But somehow I always find myself gravitating back to good old pointy-bracket mode. Maybe I am just an unreconstructed markup geek ...

Breakfast Geek-out
Breakfast Geek-out

At Westminster

At Westminster

I had a few minutes before a meeting yesterday – and so a chance to take a photo of Big Ben. The only lens I was carrying was the (small and light) Nikon E Series 50mm, which gives a slightly unusual short-telephoto focal length of 75mm (in real money) when used on a DX camera.

So, a trip over Westminster Bridge was necessary to get much into the frame.

I'm pleased with the painterly light/haze effect in this picture. That may be accounted for by the layer of dust I noticed had built up on the front element later in the day; or the software smudging caused by the slightly-misaligned frames which make up this 3-exposure HDR....