- From: Håkon Wium Lie <howcome@opera.com>
- Date: Mon, 17 Nov 2008 09:40:16 +0100
- To: "Philip TAYLOR (Ret'd)" <P.Taylor@Rhul.Ac.Uk>
- Cc: (wrong string) åkon Wium Lie <howcome@opera.com>, "public-html@w3.org" <public-html@w3.org>
Also sprach Philip TAYLOR (Ret'd): > > Yes. Draconian error handling was a mistake; it punishes users and > > rewards implementations that break the standard. A simple error > > recovery mechinanism would have made XML web-friendly and the world > > would, possibly, have been different. > > Håkon, I very rarely disagree with you, but on this occasion I > believe you are wrong. Why does one need to pander to ill-formed > content in order to be "web friendly" ? The responsibility for > producing valid XML lies 100% with the producer (yes, I know that > is a tautology) : if the producer fails in his responsibilities, > then no-one (and, even more importantly, nothing) can know what his > intentions were. Thus it is far better to say "Sorry, this document > is not valid XML; please refer to the author" There are two main problems with this, and they are related. First, users don't like to see error messages on their screens. Some think they have done something wrong, some think the browser they are using is faulty, and few will contact the author. The author will, if contacted, probably reply that "it works in other browsers". Second, UAs who implement more lenient strategies are seen to have fewer errors and are more popular both with users and authors. Therefore, as soon as one UA breaks ranks, others will follow or take grief. For UAs, it's some kind of prisoners dilemma. The first test of this that I experienced was with WML. WML is expressed in XML and UAs must therefore follow the draconian rules of XML. All UAs were starting from scratch and they were expected to follow the rules. WML was going to be much cleaner than HTML! Opera certainly followed the rules, and we still do. However, one major handset maker quickly changed its parser to be more lenient, along the lines of HTML. I can't really blame them. Noone has ever thanked Opera for sticking to the rules; rather, we've heard much grief from users and customers. Fortunately, WML didn't succeed. The grief could have been avoided with a simple XML syntax error recovery mechanism. -h&kon Håkon Wium Lie CTO °þe®ª howcome@opera.com http://people.opera.com/howcome
Received on Monday, 17 November 2008 08:41:23 UTC