Re: The Great Document Menu Debate

Dave_Raggett (dsr@hplb.hpl.hp.com)
Fri, 13 Aug 93 16:41:49 BST


David Martin says:

> What we want to be able to do is have information in the HTML header
> that indicates the structural aspects of an HTML document relative to
> some larger whole, e.g. pages w/in an article, w/in an issue, w/in a
> volume w/in a journal.

> We would then structure the documents (or whatever) menu to reflect the
> structural components of the HTML document. In general there might be a
> next, previous, and up document, but there might also be article, table
> of contents, volumes, and library links as well.

I put a lot of thought into this for HTML+ and eventually came up with what I
believe is an elegant solution. The current draft of the spec doesn't do
justice to these ideas and I intend to clarify them in the next edition.

The basic idea is to allow people to specify hierarchical structures such
as topic, sections, chapters, parts, books etc. which can spread across a
number of retrievable nodes. The next idea is to allow links between these
structures to be expressed explicitly or implicitly via rules.

When browsing a given chapter, the table of contents, glossary, etc. should
be shown as menu items (or as buttons on a toolbar), so that they are always
visible and can't be scrolled out of sight. These links are defined
explicitly as LINK elements or implicitly by the context.

Explicit links seem fine at first sight, but rapidly become tiresome for large
structures - basically the same links have to be repeated many times and
this gives rise to consistency problems. You also have difficulties when
you want to include the same node in different books etc. which would need
different links for the same properties.

Implicit links solve these problems. The "table of contents" property is
propagated to included nodes when you move between parts of the same book.
This may sound tricky, but in fact boils down to a few simple rules.

Please let me know what you think. I would very much appreciate suggestions
as to how to improve the description of these features in the HTML+ spec.

Best wishes,

Dave Raggett

p.s. the spec is available at ftp://15.254.100.100/pub as
htmlplus.ps (A4) and htmlplus8.5x11.ps (Legal)
(I will get rid of the Ctrl-D at the front of the file for the next edition).