> Date: Thu, 7 Aug 2003 09:23:57 +0100
> From: "Matthew J. Dovey" <[log in to unmask]>
> I'm trying to recall whether we said anything about returning
> diagnostics with records.  i.e. in Theo's case he could return his
> captioned records but also a diagnostic to the effect that XPath
> isn't supported.
> ditto from XML versus escaped - i.e. return what you can but also
> return an error diagnostic.]

This is a bad idea for the reasons Rob's already pointed out.

My client: Find "fruit" and give me brief summaries of the first ten
records according to this XPath, please.

Your server: Certainly, sir!  Here are ten 50Mb EAD records; oh, and
by the way, I couldn't do that XPath bit you asked me about.  Enjoy
your link saturation, sir!

> in our blasted nail example - this would be akin to the seller
> handing over a bag of size six nails and saying "we have no size 5
> will these do?"

Not really.  It's more like saying "we have no size 5, you MUST take
these size 3,546 instead, but you're allowed to throw them away as
soon as you get home".  If this is Theo's idea of "interoperability"
then we really are using the word in two totally different ways.

> Personally, I think I'd prefer to get a diagnostic xor what I asked
> for.

Yes!  Then the dialogue goes --

client: I'd like a box of number 5 nails, please.
server: Sorry, sir, we're fresh out of them.
client: In that case, I'll have number 7s.
server: Certainly, sir: here you are!
[hands them over]

I actually think hardware-store analogies are _very_ helpful in
thinking through these things, sorry Matthew!

 _/|_    _______________________________________________________________
/o ) \/  Mike Taylor  <[log in to unmask]>
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