[
Lists Home |
Date Index |
Thread Index
]
Just for a small example, how about a subset in which
elementFormDefault="qualified" and attributeFormDefault="unqualified"
are the default and only options, as the XML Namespaces spec envisioned?
Bob Foster
http://xmlbuddy.com/
Robin Berjon wrote:
> Hi Henry,
>
> Henry S. Thompson wrote:
>
>> Robin Berjon writes:
>>
>>> * 85% of XML Schema is thoroughly useless and without value;
>>
>>
>> Wow! Please identify the 15% you used -- there are lots of people
>> interested in profiling XML Schema, your input would help.
>
>
> I could identify the parts I used (elements, attributes, data types) and
> the parts I was forced to use (complex types, the small subset you can't
> get around) and while that would probably not amount to even 15% of the
> text in part 1, it would not be very useful feedback for the profiling
> you mention.
>
> To be perfectly honest regarding the feature-set of XML Schema, I am
> told and can observe myself very regularly that people are using it to
> map XML to databases, map XML to object systems, etc. and I find that
> wonderful. Few specs get to have people do so many things with them, and
> that should be celebrated.
>
> Me, I'm mostly interested in validating XML documents, or rather in the
> ability to use a schema to describe as many aspects of its instances as
> possible. And there are many aspects to a document. And, still being
> honest, I'm still waiting for the W3C spec to do that.
>
> I don't want the features in there I don't need to go away. If people
> are using them, they definitely need to stay. I do however want them out
> of my sight, because I really don't want to have to deal with them if I
> implement a schema processor. Also, I don't particularly want the
> features I feel I missing to go into a monolithic XML Schema 2.0 spec
> because I don't think that adding to the current weight is going to do
> any good.
>
> All I'm, at heart, asking for, is modularization. Cut it up into small
> manageable pieces, just like XML Schema was cut in two, but more so. And
> then we can add all sorts of small modules of interest to various
> communities. I understand the draw to have the One Schema Spec To
> Describe All XML, but that's just not possible. Admitting defeat on that
> front would be victory. The logic of interoperability seems to demand
> one spec, but there are cases in which it simply won't work out.
>
> I can't believe how much heat the binary XML people are getting with
> people saying that a generic solution can't be found there without any
> of those people bringing any proof of that to the table, while no one
> seems to notice that in a schema language, something as fundamemental as
> local determinism makes it useless to people like me, and the lack
> thereof makes it useless to others :)
>
> I think the DSDL effort gets it right by cutting things into smaller
> bits. Whether it's the right way to cut things up is a topic for
> discussion, but I really don't see how else we can go about this.
>
> There is a need for an interop spec, and that can remain the XML Schema
> spec, including a number of modules by reference. But users just need to
> pick the parts that are of use to them. Otherwise everyone will just be
> using their own 15%, and the squirrels will come back.
>
>>> * the few useful features are weak and without honour;
>>
>>
>> That seems harsh -- could you be a bit more specific? Take content
>> models (I presume they're useful) -- what's weak and without honour
>> about reconstructing sequence and choice, optionality and iteration,
>> from DTDs into XML notation?
>
>
> It is harsh, as any Klingon quote would be. You bring up notation and
> it's definitely a part of it. At a very simple level, the descriptive
> power to number of characters ratio just got lost between two keys on my
> keyboard. But I guess everyone but me and the three other people
> complaining uses IDEs and never sees the XML so it probably doesn't matter.
>
> On another level, I've created this cool vocabulary with which I'm doing
> really cool stuff on the Web. I want a schema for it because validation
> is good practice. Is there one single good reason why I should know what
> "deterministic content model" means, or even hear that sentence uttered
> if only once?
>
>>> * creating a modularized XML Schema is easier than with DTDs, but
>>> nowhere near as simple as with RNG;
>>
>>
>> Where does the difficulty lie -- notation or substance?
>
>
> Allow me to answer with a question: where in XML Schema is NVDL?
>
>>> * tools like XML Spy that are supposed to help one write schemata will
>>> produce very obviously wrong instances, meanwhile the syntax of XML
>>> Schema was obviously produced by someone who grew up at the bottom of
>>> a deep well in the middle of a dark, wasteful moor where he was
>>> tortured daily by abusive giant squirrels and wishes to share his
>>> pain with the world;
>>
>>
>> That's me (although _my_ moor was very conservative, not wasteful at
>> all :-)
>
>
> A thatcherian moor? I had no idea, I am ever so sorry :)
>
>>> * the resulting schema is mostly useless anyway as there is no tool
>>> available that will process it correctly.
>>
>>
>> Really? Xerces, .NET, saxon, XSV don't count?
>
>
> I should have dated the post more explicitly, it was about SVG 1.1,
> which came out two years ago. Things are now better (though nowhere near
> perfect). Nevertheless the amount of time it is still taking to get
> reliable interoperability between implementations of a spec that has had
> solid vendor support as few others have is an indication that something
> is wrong with the spec. I don't pretend to know exactly where, but I'm
> thinking the size and complexity of the spec don't help, especially when
> most people just exercize small parts of it. I'm pushing the notion of
> modularization (as others have before me) because I really think it's
> the only way of making this manageable.
>
> I know my post was harsh, it wasn't personal but it certainly was deeply
> heartfelt. I work for a company that uses XML Schema intensively, most
> of the time other people's schemata. I've spent literally months of my
> lifetime fixing schemata that "work in XML Spy" or "work in Xerces" but
> simply weren't compliant at very simple level. Now that the tools are
> better it's more about handling impossibly weird constructs that the
> spec tolerates and obviously natural ones that it doesn't. Whenever I
> open an XML Schema document, I twitch violently until I see
> elementFormDefault="qualified" (and then I drool a bit, but that's
> mostly for effect). Yes it's made me bitter at 28, and yes I see
> xsi:type attributes attack me in my sleep, and yes RelaxNG has had none
> of these side-effects.
>
> So please cut it down into small pieces that we can handle. *Please*
>
> I like you comparison with Java, having had a similar experience. I'm
> personally expecting to start finding it usable in three or four
> iterations. I'd just like that to happen several years earlier with XML
> Schema :)
>
|
