Re: SGML objects

Dave_Raggett (dsr@hplb.hpl.hp.com)
Wed, 18 Aug 93 13:30:40 BST


> I don't understand how this addresses the problem
> of delivering a large hierarchical document in HTML+
> chunks. Are you suggesting that I create a "master"
> document that contains entity references to the nested
> sections, each of which could be in a separate file? If I
> access the master document, would the entities be resolved
> and all the content pulled in for viewing? (Do any HTTP
> servers do that?) If so, that is the same as pulling across
> the whole book.

You would break a "book" into a number of HTML+ nodes (files)
with a "contents" node that points to the others and so on
hierarchically as needed. Entities *wouldn't* be pulled across
as you describe. Instead the user is free to follow embedded
links (as now). You can also define navigational links for
properties such as"prev/next chapter", "table of contents"
and "glossary". These links may be defined explicitly or
implicitly as described in the HTML+ spec. The advantage of
implicit links is that they avoid having to insert links
into all the constituent nodes and further allow given nodes
to occur in more than one "book".

> Also, the external files would not each be parsable SGML,
> right? They would be SGML fragments because their parent
> section containers would be in the master file. So they
> couldn't be accessed directly. I'm looking for random
> access into pieces of a large document.

Wrong! The HTML+ spec ensures that each node can conform to
the DTD regardless of its position in the wider hierarchy.
So random access to nodes is OK.

> I'm hoping the hierarchical relationships between sections
> can still be encoded in SGML, using a flatter style of
> DTD like HTML

Indeed they can.

Dave Raggett

(wishing he had made this section of the draft spec clearer!)