Re: Proposal for an Outlining Markup Scheme for HTML 3.0

Chris Tilbury (C.J.Tilbury@estate.warwick.ac.uk)
Thu, 13 Jul 1995 11:27:44 BST


From: "Chris Tilbury" <C.J.Tilbury@estate.warwick.ac.uk>
To: www-html@www10.w3.org
Date:          Thu, 13 Jul 1995 11:27:44 BST
Subject:       Re: Proposal for an Outlining Markup Scheme for HTML 3.0
Message-Id: <CF74092AE8@forest.estate.warwick.ac.uk>

On Wed, 12 Jul 1995 lee@sq.com wrote:
> HTML 3 can do this already using DIVn and Hn; what is the
> motivation for an alternative markup?

Can it? Looking at the proposal again ...

* An outline-display mechanism similar to that provided by most word 
* processors would be useful for HTML browsers.  It would allow the 
* display of large information spaces in an easy to navigate, compact 
* form.  It would also provide the user with control over which 
* information is displayed and when.  A typical use would be to display 
* a table of contents for online documentation.  It is intended to 
* provide a self-contained outline for navigating a "book" or 
* information space.  Although an entire book could be represented as 
* an outline and transmitted at once using the notation we describe, 
* this is not the notation's primary intent.

I think the key here to appreciate is that whilst the last example 
given here, that of transmitting the entire book in one go, can be 
handled by HTML 3 already and is merely a browser 
display/functionality issue, the notion of transmitting only the 
"table of contents" in an outline form cannot be sensibly handled 
by Hn and DIV.

You could certainly do

<DIV class="outline">
 <H1>This is the 1st heading in outline level 1</H1>
  <DIV class="outline">
   <H2>This is the 1st heading in outline level 2</H2>
  </DIV>
  <DIV class="outline">
   <H2>This is the 2nd heading in outline level 2</H2>
  </DIV>
</DIV>
<DIV class="outline">
 <H1>This is the 2nd heading in outline level 1</H1>
</DIV>


-  This is the 1st heading in outline level 1
   o  This is the 1st heading in outline level 2
   o  This is the 2nd heading in outline level 2
-  This is the 2nd heading in outline level 1

However, this doesn't work that well. Why?

If you attempt to use Hn is a sensible fashion, (H1 is top level, H2 
is second level, etc) you're limited to approximately 6 levels of 
outline. Whilst you may think this is enough, I can guarantee that 
there will be an application where it's not. The obvious way out of 
this is to use <P> as the container for the outline elements; viz

<DIV class="outline.entry.2">
 <P>This is the second outline level</P>
</DIV>

Later on Wed, 12 Jul 1995, brian@organic.com, continued
> I think there were presentational issues they wanted to control - to
> which I would reply this is a stylesheet issue, not an HTML issue.

I think I'd be inclined to agree with Brian here. We already have a 
mechanism for creating lists, ordered or otherwise, and for creating 
entries within these lists, and encapsulating further lists within 
these entries. I'd prefer to see (this is assuming %html.recommended)
something like

<OL class="outline">
 <LI><P class="outline.header">This is Level 1, Heading 1<P></LI>
 <LI>
  <OL class="outline">
   <LI><P class="outline.header">This is Level 2, Heading 1</P></LI>
   <LI>
	   <P class="outline.header">This is Level 2, Heading 2</P>
       <P class="outline.text">This is the text underneath L2H2</P>
   </LI>
  </OL>
 </LI> 
 <LI><P class="outline.header">This is Level 1, Heading 2</P></LI>
</OL>

We already have three list metaphor elements within the DTD, <OL>, 
<UL>, and <DL>. Another would be unnecessary, IMHO.

Regards,



Chris

--
Chris Tilbury, Estates Office, University of Warwick, UK, CV4 7AL
Tel: +44 1203 523523 x2665                   Fax: +44 1203 524444
MIME mail welcomed      mailto:Chris.Tilbury@estate.warwick.ac.uk