Re: DOCBOOK: external entities cannot be valid?

[Norman Walsh <ndw@nwalsh.com>]

/ Bob Stayton <bobs@sco.com> was heard to say:
| > You couldn't do this with SGML, either, so I'm a little
| > confused.
| 
| It's cold comfort that you couldn't do valid
| modular files in SGML either.  I thought XML was
| the *improved* version of SGML. 8^)

Er, I think it was supposed to be simpler, I'm not sure you could
get universal agreement on *improved* :-) But I feel your pain.

| > <!DOCTYPE chapter PUBLIC "..." "..." [
| > <!ENTITY chapter SYSTEM "...">
| > ]>
| > &chapter;
| > 
| > Option C is very troublesome to implement.
| 
| Ack, you are right, making a chapter wrapper file an entity
| reference to the whole content does not work, but I don't
| see why.  I presume this is because the root element of a
| valid document must be in the document before the external
| entities are processed.  But I looked through the spec but
| could not find where this type of usage is not allowed.

Production [1],

  document ::=  prolog element Misc*

The only way to satisfy element is [39],

  element ::=  EmptyElemTag
               | STag content ETag

Which can't be PE ref.

| BTW, I took a look at xinclude, and its current discussion
| of validation of merged content is a bit troublesome.

Yes. It's not cooked yet by any means.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com>      | "Bother", said Pooh, as he deleted
http://www.oasis-open.org/docbook/ | his root directory.
Member, DocBook Editorial Board    |