RE: [External] [xdi] Multiplicity questions

["Barnhill, William [USA]" <barnhill_william@bah.com>]

On the $ words for last and first elements of a collection, I proposed $first,$new,$prev, $next, and $last for the purpose of accessing collections a long time ago, which includes a $first and a $last.  If that is something that people are interested in now (there was none when I first proposed it) then I could write it up as a proposal on the wiki.

 

Kind regards,

 

Bill Barnhill

Booz Allen Hamilton - Belcamp,MD

1-443-924-0824| barnhill_william@bah.com

 

 

From: xdi@lists.oasis-open.org [mailto:xdi@lists.oasis-open.org] On Behalf Of Barnhill, William [USA]
Sent: Tuesday, July 03, 2012 2:01 PM
To: Markus Sabadello; OASIS - XDI TC
Subject: [xdi] RE: [External] [xdi] Multiplicity questions

 

If you are talking ordinal #s then taking this…

=markus$*(+email)$!1/!/(data:,aaa)

=markus$*(+email)$!2/!/(data:,bbb)

=markus$*(+email)$!3/!/(data:,ccc)

Deleting the second one would give you:

=markus$*(+email)$!1/!/(data:,aaa)

=markus$*(+email)$!2/!/(data:,ccc)

Then adding a new one would give you:

=markus$*(+email)$!1/!/(data:,aaa)

=markus$*(+email)$!2/!/(data:,ccc)

=markus$*(+email)$!3/!/(data:,ddd)

 

 

 

From: xdi@lists.oasis-open.org [mailto:xdi@lists.oasis-open.org] On Behalf Of Markus Sabadello
Sent: Monday, July 02, 2012 1:21 PM
To: OASIS - XDI TC
Subject: [External] [xdi] Multiplicity questions

 

Example:

 

=markus$*(+email)$!1/!/(data:,aaa)

=markus$*(+email)$!2/!/(data:,bbb)

=markus$*(+email)$!3/!/(data:,ccc)

 

I was wondering.. If you first delete let's say the $!2 value, and then add a new value, does the $!2 get recycled?

Or does the counter always keep going up, i.e. $!4 would be issued, even if $!2 is unused?

 

I think I-Numbers should not be recycled for new values, and new ones should always be issued.

 

So, I think an extra statement should be introduced to remember the I-Number of the last value:

 

=markus$*(+email)/$!/$!3   <-- last I-Number

 

With this statement it gets much easier and more efficient for the server to add a new value of +email.

 

Or perhaps it would be even better to used GUID-style I-Numbers, then the question of increasing the counter becomes obsolete.

Or perhaps the spec should not specify this, i.e. you could either use sequential I-Numbers, or GUID-style ones, whatever you prefer.

 

At XDI2 we need this for implementing link contracts and the policy context nodes, which use the multiplicity format.

 

If this looks right, I'll create a Proposal page.

 

Markus