RE: Starting the ietf-xml-mime mailing list

["Gavin Thomas Nicol" <gtn@xxxxxxxxxxxx>]

> 1. something generic gets the XML and parses it
>  1.a the generic something displays the XML to a human using a 
>      stylesheet, possibly with help from other logic for 
> embedded chunks
>      from different namespaces.
>  1.b the generic something invokes some application.
> 
>  The 1.a example is of course Web browsers (although it seems there 
>  are some nasty architectural holes in how you dispatch control for 
>  embedded chunks of XML).  I have a hard time thinking of a 1.b
>  example.
> 
> 2. An app gets invoked to deal with a resource that happens to
>    be encoded in XML, and the app uses its built-in XML parser.
>    This case probably wants its own media type; the fact that 
>    the encoding is XML is hardly material.

I would say that 1b is roughly equivalent to 2, except for an additional
level of abstraction.

I actually prototyped, a while ago now, 1b using the standard set of
mail tools on Unix. I basically specified a compound document/application
object in a TR9401 catalog (a poxy medium it turns out, that needed a lot
of fixing, and a number of extensions). That catalog could be transmitted
to a generical application that then invoked whatever else was appropriate
(in this case, DynaText, Panorama, and Web browsers).

I think we need to clearly seperate the issue of packaging a single XML
instance/entity, and a compound document. I would argue that the former
is almost entirely devoid of any application semantics (being either
simple text/xml or application/xml), but the latter *intrinsically*
has *some* semantics associated with it.

I guess this is basically supporting the notion that application specific
uses of XML should have application defined media types, but there is a
slight difference in the *mechanism* that I am talking about. We could
have something like xml/processing-specification or something suchlike,
with an associated handler, and that handler could be reponsible for the
dispatch (not part of the MIME world at all). Again, I prototyped something
like this some time ago, and it did work well,  even on top of *existing*
(this was '95) MIME infrastructure.

I should note that both Simon St. Laurent and Chris Lilley have been making
noise about such "catalogs" recently as well.