That would break UBL NDR rules of
course.
I think we'd need to start a whole new
discussion in UBL on this and that
would
probably take more time than we have.
I remember we discussed it in Hong
Kong
and decided we need the minor version
namespace changes.
I have seen the problems you get when
the minor versions don't have
namespace
changes and they are highly regretable.
I'd
hate to think of not learning at all from
history.
Then of course there is the option that
we
don't have minor versions and that
seems
a catastrophic departure from all UBL
has
achieved so far (IMO).
Steve
----- Original Message -----
Sent: Tuesday, July 19, 2005 10:47
AM
Subject: Re: [ubl] Discussion of
substitution groups
And if we don't minor version our namespaces? Mark R.
Crawford Senior Research Fellow - LMI XML Lead W3C Advisory Committee
and OASIS Representative, Vice Chair - OASIS UBL TC Vice Chair -
UN/CEFACT Applied Technologies Group Chair - UN/CEFACT XML Syntax Working
Group Co-Chair ISO TC154 Subcommittee for ISO 15000-5 -- LMI
Government Consulting 2000 Corporate Ridge McLean, VA
22102-7805 703.917.7177 Phone 703.655.4810 Wireless The opportunity
to make a difference has never been
greater www.lmi.org
-----Original Message----- From: Stephen
Green <stephen_green@seventhproject.co.uk> To: CRAWFORD, Mark
<MCRAWFORD@lmi.org>; ubl@lists.oasis-open.org
<ubl@lists.oasis-open.org> Sent: Tue Jul 19 04:11:01 2005 Subject:
Re: [ubl] Discussion of substitution groups
I believe we need to use
substitution groups for minor versioning as per NDR Rules VER 8 and VER 9,
to allow use of imports of previous versions' schemas and xsd
derivation. I believe this has been an important part of the NDR design
from the beginning of UBL, it having been intended since then that minor
releases and customisations would use XSD-enabled inheritance
and polymorphism. The reason the above requires substitution groups to
make it work in UBL is the highly structured, type oriented and essentially
complex nature of UBL. I believe it would be impossible or at best far more
difficult to achieve the same aims with a local schema design, This, I
believe, was the main reason for the use of the global element and global
type design. I also now believe it would be impossible or very difficult to
achieve the same goal using XSD redefine (or any other XSD method
for that matter). (IMO) the only choice might be whether to use abstract
elements and types, forcing substitution and I see nothing to be gained and
much possible confusion from this so I personally would rather avoid it, as
we did with the design we recommended to the TC from the UBL
minor versioning [ver] working group in April. Thankfully, Marty has
well demostrated that a working design for substitution group use without
abstracts can be used for codelist extension too.
Overall, in just a
few words, we need it for XML with XSD to be properly eXtensible in
UBL.
All the best
Steve
----- Original Message
----- From: "CRAWFORD, Mark" <MCRAWFORD@lmi.org> To: "Stephen
Green"
<stephen_green@seventhproject.co.uk>; <ubl@lists.oasis-open.org> Sent:
Monday, July 18, 2005 4:08 PM Subject: RE: [ubl] Discussion of substitution
groups
> This all the more persuades me that for >
minor versioning and codelists we have > only one sensible option -
substitution > groups (without use of abstracts).
But if our
schema follow our NDRs and are created from models as expressed in the
spreadsheets, why do we need to use substitution groups at
all?
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