Re: [xdi] Re: again on numbering..

From
Markus Sabadello <>
Date
2008-01-29T19:05:12+00:00
ID
Thread
Re: [xdi] Re: again on numbering..
Heya Peter,

 

Hmm maybe there's a misunderstanding.. When I wrote lines like this:

 

=markus/+email!1/""

 

..I didn't mean this as an identifier that points somewhere. It's a very short way of writing down XDI data itself that's stored at some endpoint (e.g. at =markus' XDI endpoint)

 

The same data in X3 would be [=markus[+email!1[""]]].

 

A POINTER to that data would look exactly as you propose I think, e.g.

 

=markus/+email!1

 

So there's no literal in the identifier itself, only in the XDI document the identifier points to.

 

Does that make any sense?

 

Markus
 

On 1/29/08, Peter Davis <> wrote:
A general observation wrt the X3 graphs being proposed here:

I am seeing an increase in the discussions were predicate values are

being explicitly declared in the XRI productions.  I think this
approach can be wrought with peril...

My concern revolves around the exposure of communication endpoints in
identifiers.  This was a property that made XRI's to me very

compelling.  I can share some concrete identifier (and a path into,
for example, to a predicate eg: xri://=peterd/+email) without
exposing the email literal.  rather, a service endpoint which might
handle XDI (for example) requests can apply some set of security

policies before responding with some (if any) values. Out of
curiosity, why would i want to express the value of a predicate in
the identifier itself (rather than a pointer to it's value)?

Here i am seeing attributes of identity being regularly used in the

identifiers, and thus the privacy properties of the communication
endpoints are lost.

I realize that i have not been active on this list for some time, and
so i may be taking the use of the identifiers being expressed here

out of context, but if my interpretation of this discussion is
correct, i see what i think is a misuse of XRI as an address into my
attribute graph.

my .02

=peterd

On Jan 29, 2008, at 12:41 PM, Markus Sabadello wrote:

> Heya Giovanni,
>
> I think the idea of having a way to express ordered collections in
> XDI would be very useful...
>
> We came across a similar problem a few days ago.. How do we express

> multiple values for a predicate? For example, =markus could have
> multiple e-mail addresses. We came up with the following idea:
>
> =markus/+email!1/""

> =markus/+email!2/""
>
> But your pattern would work too:
>
> =markus+email/$num$1/""

> =markus+email/$num$2/""
>
> A third idea Drummond had was to use inner graphs, like this:
>
> =markus
>     +email

>         /
>             $
>                 $1
>                     ""
>                 $2
>                     ""

>
> I like all three methods.. But we should probably decide on one of
> them.. Or just experiment for a while and see what works best...
>
> Markus
>
> On 1/29/08, Giovanni Bartolomeo <>

> wrote: Hello,
>
> some new inputs about this issue:
>
> >* Markus asked if $num is always used in conjuntion with $has
> predicate, or
> >if there would be other uses? Giovanni said it would also be useful

> >standalone.
>
> I think that $num could be useful also in accessing arrays, vectors
> and similar structures what we could call "ordered collections".
>
> Let's consider again this use case:

>
> =football.team/$has$num$11/+player
> @as.roma.calcio/$is$a/+football.team
>
> we could index each player using $num${x} as follow:
>
> @as.roma.calcio+player/$num$0/=curci
> ...

> @as.roma.calcio+player/$num$7/=derossi
> ...
> @as.roma.calcio+player/$num$10/=totti
>
> etc.
>
> Do you think this capability could be of help for XDI?
>
> BTW maybe we can avoid the prefix $num and leave only ${num}, e.g.

> $0, $5, $7 are valid XRIs which represent the number 0, 5, 7.
>
> What do you think?
>
> Bests,
> Giovanni
>
>
>
>