RE: Syntax Sugar and XML information models

[John Aldridge <john.aldridge@informatix.co.uk>]

At 21:13 28/03/2001 -0500, Michael Champion wrote:
>So, does ANYBODY care about round-tripping a) the specific quote characters
>around attribute values, b) the order of attributes; c) character entity
>references for characters that are in the specified character set d) the two
>diferent syntaxes for empty elements, .... ?

Yes, but only sometimes.  I _do_ mind if editors unpredictably change these 
things, because I'm going to store XML data in RCS, and expect rcsdiff, 
rcsmerge & the like to do sensible things.

Actually, from this point of view, there are two workable solutions:

(a) Editors don't change syntax sugar, except when the user edits something 
at or near the place in question, or
(b) Editors all write a _standard_ normal form (i.e. not just a normal form 
of their own choosing)

I've been here with HTML before, for example:  the HTML editors AOLpress 
and FrontPage Express both normalise the HTML they write in some respects, 
but to different rules.  So if some developers edit technical documentation 
using AOLpress and others prefer FrontPage Express, this makes the RCS 
differencing tools essentially useless.

Whatever, I prefer (a), for much the same reasons as I wouldn't want to use 
a "C" source code editor which always pretty-printed its 
output.  Indentation and the like should be under my control.

You said it yourself...

>So, there seem to be two classes of things that the InfoSet doesn't cover:
>the "mere syntax" that no reasonable application (except maybe a "diff")
>would care about

except that I think this is an important application, not one which should 
be swept under the carpet.

However...

I'm in full support of the goals of the infoset:  I want agreement on the 
significant information content of an XML file.  The XML spec itself 
started on this road in various areas, such as attribute value 
normalization -- the infoset is finishing the job.

It's just that some applications need to operate directly on the 
representation, and not just on the information.

-- 
Cheers,
John