Re: Dates in XML

Ron Bourret (rbourret@dvs1.informatik.tu-darmstadt.de)
Fri, 10 Jul 1998 17:38:18 +0200

Peter Murray-Rust wrote:
> ...
> I was looking at the XML-Data proposal just today and thinking 'why don't
> we use the primitives it defines, just as they are, without the rest of
> XML-data?'. This encourages me to offer the question to a wider audience. I
> am seriously missing a specification for primitives - what do other people
> think about borrowing those from XML-data?

Absolutely. For XSchema 1.1, I vote for a dt:dt attribute on the PCData
element.

The XML-Data spec shows the following ways to specify data types:

Attribute: <size dt:dt="int">8</size>
Subelement: <size><dt:int>8</dt:int></size>
Schema: <elementType id="size"><datatype dt="int"/></elementType>

I believe we should only adopt the first of these for now.

While there are no technical problems with the second, it seems counter to the
spirit of XML: We are now most closely labeling the value 8 as an int, rather
than as a size, which is what it really is.

The third is just plain confusing because the datatype subelement is not part of
the content model. For example, what does the following XML-Data declaration
mean? The sequence is an integer? I can imagine datatype elements as a
substitute for content models, but not in addition to them. Anything I'm
missing here?

<elementType id="size">
<datatype dt="int">
<group groupOrder="SEQ">
<element type="#shoe"/>
<element type="#shirt"/>
</group>
</elementType>

-- Ron Bourret