- From: Dan Holmsand <dan@eyebee.com>
- Date: Sun, 12 May 2002 16:09:47 -0400 (EDT)
- To: "Kay, Michael" <Michael.Kay@softwareag.com>
- CC: public-qt-comments@w3.org
Thanks for the prompt reply! Kay, Michael wrote: > Thanks for the comments. You're not alone in finding XML Schema Part 1 > difficult to digest. Clearly in writing specs it's not our job to produce a > tutorial, but we can certainly bear your comments in mind. In particular, I > think we probably need to be clearer about how processing happens in the > absence of a schema: at the moment we rather rely on people knowing that > this is just a special case of the PSVI, and the specs concentrate on > describing the general case which is of course much more complex. I (of course) agree that the spec should not be a tutorial. On the other hand, it is quite handy to be able to tell people to consult the spec when they've made a mistake. You can do that with XSLT/XPath 1 (and, when the time comes, with the XSLT part of the new spec). But you can't very well tell people to go have a look at e.g. www.w3.org/TR/query-semantics before they ask any more stupid questions. Can you? > I think some features of the XPath 2.0 type system are things you are just > going to have to live with. The introduction of sequences, I think, brings > many benefits. The expansion from the three scalar types (boolean, double, > and string) of XPath 1.0 to the 19 primitive types of XML Schema is a larger > expansion than many of us would have liked, but many of the primitive types > will hardly ever be used so you will be able to ignore them most of the > time. Complex types arise only when using schemas, and again I hope we can > ensure that when you don't use a schema, you don't really need to be aware > of them. This is where we don't agree. I have never really bought the "you don't have to pay for what you don't use" argument when it comes to C++ (another incredibly complex language): before you know it, you have to understand or maintain other people's code. If they use the complexities you've decided to do without, you have to pay anyway. I fear the same will apply to XPath 2. > There will probably be a conformance level in XSLT 2.0 that doesn't require > schema support; defining conformance levels is something we have not yet > tackled. That's really good to hear! I just hope that the conformance level isn't just provided for the benefit of lazy implementors, but for lazy users as well (and by lazy I mean those who can't/don't want to learn everything about XML Schema and its data types). For example: A "disable-schema='true'", or "version='2.0-light'", instruction in XSLT would tell me that this is an XSLT stylesheet that I can understand, and it is a requirement that I can communicate to others. /dan
Received on Wednesday, 15 May 2002 15:26:22 UTC