RE: Fwd: [xml-dev] Data versioning strategy: address semantic, re lation

[noah_mendelsohn@us.ibm.com]

Len Bullard writes:

> Please elaborate on the shades of gray.

I'm a bit worried that our exchange may be going on long enough to be 
bothersome to other readers of the list, but sure:  all I meant by shades 
of gray is what was captured in my "country code" example.  Is that 
country code in the accept set or not?  It's clear that for certain 
purposes it is completely incompatible.  If you try to dial the phone 
number without the country code, then you will have unaccetable 
consequences.  So, probably it's not in the accept set.  Then again, I 
proposed rules that would make that same country code acceptable for many 
other important purposes.  We're not even going to completely ignore it: 
we'll save it with the purchase order, pass it on if we relay the order, 
sign it with a DSIG, maybe even use some default rules for extension 
content to print it along with the rest of the phone number. 

So, all I meant by "shades of gray" is that compatibility is in that sense 
a matter of degree.  Some language that provide for extension content also 
provide default interpretations for that content.  Furthermore, many 
applications that accept extensible languages as input have default rules 
for processing or manipulating that extension content.  Awhile ago I wrote 
a note on this topic on the TAG mailing list.  If you're interested, it's 
at [1].  There's been sporadic followup discussion but no easy consensus 
on how to think about these things.  By the way, I give in that note my 
understanding of Tim BL's positions on certain things;  I don't think he's 
confirmed that I understood him correctly, so please don't blame him for 
things he didn't (necessarily) say.

Anyway, if I were another reader of this list I'd probably be anxious to 
see this bit of the exchange wrap up, so I propose we let it go and give 
others a chance to chime in.  Of course, I'll be glad to keep going if 
that's for the best.  Thanks.

Noah

[1] http://lists.w3.org/Archives/Public/www-tag/2007Jun/0092

--------------------------------------
Noah Mendelsohn 
IBM Corporation
One Rogers Street
Cambridge, MA 02142
1-617-693-4036
--------------------------------------








Len Bullard <len.bullard@uai.com>
12/14/2007 06:03 PM
 
        To:     noah_mendelsohn@us.ibm.com
        cc:     Greg Hunt <greg@firmansyah.com>, xml-dev@lists.xml.org
        Subject:        RE: Fwd: [xml-dev] Data versioning strategy: 
address semantic, re     lationship, and syntactic changes?


Please elaborate on the shades of gray.  I didn't get that obviously, and
apologies to Dave.

IMO, there is nothing wrong with the set approach other than it might be
insufficiently detailed and in cases where it matters, non-dynamic.  I
haven't been a subscriber to the TAG list for the last year so I've no
currency with respect to the discussions there.  For me, this is a 
partially
theoretical discussion in that I consider code versioning a *tools* 
problem
(eg, integration of CVS and Microsoft tools can be strange).  On the other
hand, the applications of dynamic systems theory to the problem interests
me.  It is a neat problem and 'tuning' solutions seem to be applicable.

len


From: noah_mendelsohn@us.ibm.com [mailto:noah_mendelsohn@us.ibm.com] 
 
Len Bullard writes:

> It may be possible to take Noah's sets and combine these into a formula

I don't recognize the set formulation as being mine.  They are one of the 
approaches being tried as the TAG works toward a finding on versioning, 
but of all the TAG members I am probably among the less enthusiastic about 

the approach, in part because I don't yet see how it deals with the shades 

of gray that I outlined in my note earlier today.  I'm not hard over 
against the set approach either, just trying to see how it works out.  In 
nay case, I think it was Dave Orchard who advocated the set-based approach 

on in this xml-dev thread.

Noah

--------------------------------------
Noah Mendelsohn 
IBM Corporation
One Rogers Street
Cambridge, MA 02142
1-617-693-4036
--------------------------------------



This email and any files transmitted with it are confidential and intended 
solely for the use of the individual or entity to whom they are addressed. 
If you have received this email in error please notify the sender. This 
message contains confidential information and is intended only for the 
individual named. If you are not the named addressee you should not 
disseminate, distribute or copy this e-mail.