Re: HTML+ and printed books

Dave_Raggett (dsr@hplb.hpl.hp.com)
Wed, 19 May 93 13:46:03 BST


>> The obvious structuring element corresponds to the contents list, e.g.
>>
>> <CONTENTS>
>> <A HREF ="doc1.html">Introduction to home brewing</A>
>> <A HREF ="doc2.html">Equipment Needed</A>
>> <A HREF ="doc1.html">The basic skills</A>
>> <A HREF ="doc1.html">Popular recipes</A>
>> </CONTENTS>

> Would these be top level headings? I think a level indication is
> appropriate in this case, so instead you'd have entries like:

> <A HREF ="doc1.html"><H1>Introduction to home brewing</H1></A>

No, it would be an abuse of the concept of what a header is. To specify
the level of each entry you really need another mechanism.

(By the way your example is bad practice - the header tags
should include the anchor element - not the other way round)

I have been studying fiction, reference books, various types of technical
documentation, magazines and newspapers to get a deeper understanding of
what presentation independent markup is needed. It now seems to me that
A more explicit mechanism is needed which includes tags for chapters,
sections, and subsections etc. The analysis looks really encouraging and
I am working out how to fit it into the DTD.

> While this make sense in a printed world where each chapter (node) only
> appears in one book (for the most part), it doesn't make sense in the
> hypertext world where a node can potentially occur in as many books as
> people can dream up. It would be up to the browser software to keep track
> of the current book or books that you're browsing through. The model would
> be that an on-line book is just another "view" into the information space.
> I think that this is a powerful and useful notion.

I remember discussing this point with Tim Berners Lee in a trip to CERN last
year. Users will want to exploit the table of contents view and the ability
to print out collected chunks from arbitary points. This suggests the need
to define links from the currently viewed document to such elements.

Hypertext links from outside into particular sections of an on-line book
are normally consistent with the notion of following references between
books - it doesn't change what the user expects to get printed. It is only
in the case where you have books which "borrow" sections from other books
that the trouble occurs.

Reconciling these two models can be achieved by:

a) normal links don't change the "standard" association between
a retrievable chunk and an on-line book/magazine/newspaper etc.
as defined by <LINK REL="CONTENTS" HREF="contents.html">

b) links which have the effect of borrowing sections from other
books are special and override the "standard" association.

These special links could be designated by the REL attribute in the <A> tag.

e.g. <a rel="borrow" href="http://foo/bar">A borrowed section</A>

Best wishes,

Dave Raggett,

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