[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]
Subject: RE: [xri] Potential breakthrough
Marty, I think I understand the point you are trying to make. However
I believe there’s a logic flaw in this scenario. You first posit that
Boeing assigns @boeing*123 as the identifier of a mountain. You then posit that
since Ootao got a radio transmitter for an owl from Boeing, Ootao in its own
context (@ootao) would give that radio transmitter the XRI “@boeing*123”,
creating the composite XRI @ootao@boeing*123. But why would Ootao do that when it knows that the
identifier “@boeing*123” has been assigned to a mountain? While it’s
entirely _possible_ for Ootao to decide
it wants to assign the identifier Boeing uses for a mountain (@boeing*123) to
an radio transmitter, Ootao would be asking for trouble doing that because
everyone else who wants to understand the identifier @boeing*123 means could go
to @boeing to ask what it means and find out it identifies a mountain. Ironically, this ends out illustrating precisely the
difference between using @boeing or *(@boeing). If ooTao wants to set up its
namespace as you described, and assign Boeing-built radio transmitters
numerical identifiers _without_
any chance of confusion with XRIs assigned in Boeing’s own namespace,
Ootao could construct the algorithm: @ootao *(@boeing) *sequence-number-of-radio-transmitter This would yield @ootao*(@boeing)*123. Now there’s no
chance of confusion with @ootao@boeing*123. =Drummond From: Schleiff, Marty
[mailto:marty.schleiff@boeing.com] Drummond, I didn't switch places at all. The place
where I've camped all along is the same place I continue to camp. The context
of every XRI subsegment must be unambiguously clear, and your newest idea
muddies the waters more than ever, as illustrated by the following fictional
story: Here are pictures of two objects: 1)
/\/\/\/\ (a mountain range) and 2) oVo (an owl). A Boeing project requires
fully-qualified identifiers for mountains, and Boeing has assigned
"@boeing*123" to /\/\/\/\. The Boeing managed XRDS service
points for /\/\/\/\ deal mostly with GPS coordinates and elevations (so
Boeing-built planes won't crash into mountains). An Ootao project requires fully-qualified
identifiers for owls, and the naming convention they follow includes a reference
to the manufacturer of the radio transmitter attached to an owl's leg. The
transmitter on oVo was manufactured by The Boeing Company, and oVo got the
123rd Boeing-built transmitter that Ootao has put onto an owl's leg. So Ootao's
fully qualified identifier for oVo is "@ootao@boeing*123". The Ootao project tracks various habitats
for owls, and Ootao is interested in /\/\/\/\ because lots of owls live
there. Ootao's is interested in the GPS coordinates, elevations,
vegitation, prey, and weather conditions in mountain ranges. Ootao brings
"@boeing*123" into an Ootao context as "@ootao@boeing*123"
(so Ootao can include the Ootao-managed service points dealing with vegitation,
prey, and weather data in the XRDS). BTW, oVo (known as "@ootao@boeing*123")
doesn't live anywhere near /\/\/\/\ (also known as
"@ootao@boeing*123"). Marty.Schleiff@boeing.com;
CISSP From: Drummond
Reed [mailto:drummond.reed@cordance.net] Marty, This is ironic. As you expected, my answer
to both would be @ootao@boeing*reputation. But whereas now I’m satisfied
that this *doesn’t* have any
problems, you now believe it does. How did we switch places so fast? ;-) I’ll explain why I believe it
doesn’t, and then you can explain why you believe it does. The reason I formerly believed that
“@boeing*reputation” needed to be “opaque”, i.e.,
recognizeable as a single identifier by an XRI parser, was that it might be
“misunderstood” when placed in another context if it didn’t
“stick together”. However once I revisited that assumption, I
realized that “@boeing*reputation” asserts exactly three things: 1) The reassignable identifier
“boeing” is an a global organizational context (@). 2) The reassignable identifier
“*reputation” is in a local context (*). 3) The reassignable identifier
“*reputation” is in the context of the identifier @boeing. Now, when we place @boeing*reputation in
the context of @ootao to get @ootao@boeing*reputation, it tells us exactly five
things: 1) The reassignable identifier
“ootao” is an a global organizational context (@). 2) The reassignable identifier
“boeing” is an a global organizational context (@). 3) The reassignable identifier
“*reputation” is in a local context (*). 4) The identifier @boeing is in the
context of the identifier @ootao. 5) The identifier
“*reputation” is in the context of the identifier @boeing. This all seems very straightforward to me
now. By eliminating the “sticky star” rule, the interpretation of
the XRI “grammar” rules you have been asking me for just got a lot
easier. (I’m glad I hadn’t tried to write them yet, because I saved
myself a lot of time ;-) What am I missing? =Drummond From: Schleiff, Marty
[mailto:marty.schleiff@boeing.com] Hi Drummond (& All), I'm not sure I understand what you're
suggesting, so I'm seeking confirmation. 1) How do you propose to represent
"@boeing*reputation" in the context of "@ootao"? 2) How do you propose to represent
"*reputation" in the context of "@ootao@boeing"? If your answers to #1 and #2 are the same,
then we've still got problems. Marty.Schleiff@boeing.com; CISSP
From: Drummond
Reed [mailto:drummond.reed@cordance.net] I have an internal maxim that I follow: if Steve tells me
he’s got a problem with something, and after three times trying to work
it out with him, he’s still got a problem with it, then I need to look at
it very closely and see if there’s a better solution. I’ve worked long enough with Marty now to realize the
same thing is true with him. So when both of them plus Wil are telling me something is
too complex, that’s one helluva strong signal. So after yesterday’s thread, I looked closely at the
requirements again and thought about the key issue Steve has raised about how
“sticky stars” makes for funky synonym rules. This jibes with what
Marty keeps saying about how the original “compact syntax” was much
simpler than “sticky stars”. I have always been the one saying that we needed sticky
stars. So I revisited that assumption…and realized that in that area I
too had been stuck with a “2.0” filter on. I had been assuming that
anything you could express as a parenthetical xref (which is
“opaque” to XRI resolution) had to be something that was also
equally “opaque” when expressed as a global-xref. But it’s that assumption that leads both to most of
the increased complexity and the funky synonym problem. So if you drop that
assumption and do as Marty has been suggesting all along and simply treat all
subsegments as subsegments… …everything works just fine. To illustrate, take Steve’s @ootao+west*steve and
@ootao*west*steve example. The current 2.1 syntax proposal requires these parse
into separate trees: @ ootao +west*steve @ ootao *west *steve But if you drop the requirement that global-xrefs need to be
syntactically opaque, they would both parse into the same trees, with the only
difference being the type of one subsegment: @ ootao +west *steve @ ootao *west *steve The funky synonym problem goes away because all subsegments
are subsegments, and if @ootao wants to declare +west and *west as synonyms, it
doesn’t affect any other synonyms lower in the tree. But you still get
the semantic precision of @ootao being able to express that +west is intended
to be a generic dictionary identifier vs. *west a local name without any
expectation of cross-referencability. So I tried to figure out if there was any other requirement
– in XDI RDF or anywhere else global-xrefs would be used – that
would not be met if global-xrefs were not opaque. I couldn’t come up with
any. If so, we could essentially have our cake and eat it too.
The ABNF would get significantly simpler, and we’d get all the semantic
simplicity/richness of direct concatenation, but without any of the pain of
funky synonyms or increase resolution complexity. Frankly, I’m still trying to figure out why I was so
stuck on “sticky stars” (so to speak ;-). After all, Marty has
repeatedly said things would be much simpler without them. But then, sometimes
when something’s stuck in your head, it takes a real jolt to knock it
out. I’ll take a pass on the simpler ABNF that reflects all
this as soon as I get a break today – worst case I’ll try to have
something published by tonight. =Drummond |
[Date Prev] | [Thread Prev] | [Thread Next] | [Date Next] -- [Date Index] | [Thread Index] | [List Home]