From: Ralph Hartley (hartley_at_aic.nrl.navy.mil)
Date: Fri Feb 09 2001 - 14:45:34 CET
Received: (from mdom_at_localhost) by karto.ethz.ch (8.9.3/8.9.3/SuSE Linux 8.9.3-0.1) id OAA06079 for cavexml-outgoing; Fri, 9 Feb 2001 14:41:47 +0100 Received: from sun0.aic.nrl.navy.mil (sun0.aic.nrl.navy.mil [132.250.84.10]) by karto.ethz.ch (8.9.3/8.9.3/SuSE Linux 8.9.3-0.1) with ESMTP id OAA06075 for <cavexml_at_cartography.ch>; Fri, 9 Feb 2001 14:41:46 +0100 Received: from aic.nrl.navy.mil (pc31.aic.nrl.navy.mil [132.250.84.181]) by sun0.aic.nrl.navy.mil (8.9.3+Sun/8.9.3) with ESMTP id IAA22182 for <cavexml_at_cartography.ch>; Fri, 9 Feb 2001 08:42:29 -0500 (EST) Message-ID: <3A83F47E.9060605@aic.nrl.navy.mil> Date: Fri, 09 Feb 2001 08:45:34 -0500 From: Ralph Hartley <hartley_at_aic.nrl.navy.mil> User-Agent: Mozilla/5.0 (X11; U; Linux 2.2.16-22 i686; en-US; m18) Gecko/20010124 X-Accept-Language: en To: cavexml_at_cartography.ch Subject: Re: defaulting units for measurements References: <Pine.GSO.4.05.10102081531270.5063-100000_at_cor.oz.cc.utah.edu> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-cavexml_at_karto.baug.ethz.ch Precedence: bulk Reply-To: cavexml_at_cartography.ch
John Halleck wrote:
> On Thu, 8 Feb 2001, Ralph Hartley wrote:
>
>> <property from=<station name="1"\> > <!-- Syntax for an element as value of a field? --!>
>> <property to=<station name="2"\> >
>
>
> Excuse me? The above aren't even wellformed XML.
>
> I'm having trouble telling what was actually intended...
> (You can't have "<" and ">" inside of a Start tag.)
I knew it might not be. I should have looked it up. That's what you get
when you write code for an unfamiliar language in public.
Read that as:
<property from="1">
<property to="2">
Wherever you see <station name="string"\n> in either of my emails from
yesterday read that as "string".
It was bad form to try to make more than one point at a time, I was
trying to illustrate the idea of "modality" dependent, nested defaults.
The simpler form (besides being correct) would have been more clear for
that point.
The other point was that there really needs to be more to a station than
just a name. Names might be assumed to be unique, but we all know they
never are. If names are to be disambiguated by context, it needs to be
made clear how.
I assumed that XML allowed nesting of a kind that it apparently does not.
It looks like the only the way to do what needs to be done here is for
the values of the "from" and "to" attributes to be IDREFs that
(uniquely) identify a "station" element, that can be defined anywhere in
the document, but might need to be defined in a particular place if it
needs context as part of its name.
My other email yesterday, had an illustration of why from="stationname"
is not enough. In processed data, a station may have two (or more)
locations, due to unclosed loops. There needs to be a way to specify
which of those a shot connects to.
Ralph Hartley
This archive was generated by hypermail 2b30 : Thu Mar 01 2001 - 18:00:00 CET