If you are going to 'include' binary 'files' (i.e. entities) then it gets
more complex. This is my current analysis. It's probably wrong. (Are there
any Java parsers which manage this?)
<!DOCTYPE CML [
<!NOTATION GIF
PUBLIC "+//IDN ds.internic.net/rfc/rfc2046.txt//NOTATION
Multipurpose Internet Mail Extensions::image/gif//EN">
<!-- I hope I have copied that right - please don't sue - typos are likely -->
<!ENTITY mygif SYSTEM "my.gif" NDATA GIF>
<!-- an ENTITY declaration is required for EVERY image??? -->
<!ELEMENT CML (IMG)*>
<!ELEMENT IMG (EMPTY)>
<!ATTLIST IMG SRC NOTATION (GIF) #REQUIRED> <!-- I could include JPEG, etc-->
]>
<CML>
<IMG SRC="mygif">
</CML>
This is all required for one GIF. Every GIF requires an ENTITY. There
*must* be an internal subset. There must be a registry for the FPIs, etc.
In XLL I can write a complete document:
<CML>
<IMG HREF="my.gif" XML-LINK="SIMPLE" SHOW="EMBED" ACTUATE="AUTO"
MIME="image/gif"/>
</CML>
(excuse the case insensitivity)
>It would be nice if there was also an "inline" way of doing includes
>that would allow the XML parser to validate the resulting content.
Well, XLL does this ***as long as we agree on the semantics***. HREF (or
IMG/SRC) is so widely used in HTML that people will certainly start doing
their own thing. There are the following possibilities:
- wait for a W3C body to pronounce (won't be this year, I suspect)
- wait and see what commercial browsers do
- invent nine-and-sixty ways of doing it
- use XDEV: as at least a means of coordinating *some* people.
JUMBO will start with the latter, and junk it as soon as anything official
comes along...
[BTW I am not very happy with the idea that FPIs are intended to be human-
but not machine-readable. That makes them useless for things like image/gif.]
P.
Peter Murray-Rust, Director Virtual School of Molecular Sciences, domestic
net connection
VSMS http://www.nottingham.ac.uk/vsms, Virtual Hyperglossary
http://www.venus.co.uk/vhg