New Issue: name for the urType

I would like to raise a new issue for consideration in last call of XML
schema.  I think this request is based on new information, and I request
that it be placed on our list for consideration.

As James Tauber has noted, we do not have an explicit name for the urType.
The new information is that, during the design of the latest SOAP
specification [1], we realized that even if the schema language itself can
get by without a string name for the type, other systems have real need for
such a name.

In a nutshell, SOAP has its own mechanisms for declaring array-like
structures beyond those currently offered by schemas themselves.  So, you
will see SOAP elements labeled with attributes like:

     SOAP-ENC:arrayType="xsd:int[3]"

which refers to an array encoded as three XML elements each of which is
conformant with xsd:integer.  Or:

     SOAP-ENC:arrayType="yourNS:address[3]"

I happen not to be thrilled with that particular syntax, because I would
prefer explicit markup and not to have QNames buried within a string, but
neither of those is the issue here.  The requirement is for some means of
saying things like:

     SOAP-ENC:arrayType="xsd:urType[3]"

to indicate an array of three elements each of which must be a (subtype of)
our urType.  As with our schema design, the intention is to allow both
simple types and complex types in the instance, so it is truly is our
notion of urType.

I believe that SOAP is not the only system that will emerge with such a
requirement.

If we as a workgroup decide not to provide such a name for the type, then
it is likely that SOAP will wind up defining something like SOAP-ENC:urType
with an indication that it refers to the urType of XML schemas (indeed,
that was supposed to make it into the SOAP 1.1 specification and didn't
quite because the problem was noticed too late.)  I think everyone involved
believes that would be undesirable.  So, the request is for an
officially-blessed name for the urType.  (Note: this is not a request to
try to split into separate urTypes for simple and complex... just a name
for what we have got.)

By the way, I think most ordinary mortals will find the term urType to be
unduly obscure.  Perhaps something like "xsd:base"?  I'm sure we could
amuse ourselves with a little name-the-urType contest.  Thank you very
much.

[1] http://www.ibm.com/software/developer/library/soap/soapv11.html

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Noah Mendelsohn                                    Voice: 1-617-693-4036
Lotus Development Corp.                            Fax: 1-617-693-8676
One Rogers Street
Cambridge, MA 02142
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Received on Friday, 28 April 2000 19:28:49 UTC