- From: Russell Steven Shawn O'Connor <roconnor@wronski.math.uwaterloo.ca>
- Date: Fri, 20 Mar 1998 00:25:43 -0500 (EST)
- To: www-html@w3.org
Future of HTML
File location:
<URL:http://www.undergrad.math.uwaterloo.ca/%7Eroconnor/HtmlArch.html>
Proposer contact: roconnor@uwaterloo.ca
Name: Russell O'Connor
Tel: 204-753-2440
_________________________________________________________________
HTML Architecture
By: [1]Russell O'Connor
Most authors use an SGML document type definition to define a
document's class. The problem is that DTDs can only define
document syntax rules. DTDs cannot define the semantics of a document.
In order to properly define a document class, authors should use an
SGML architecture. Authors can declare that their documents conform to
an SGML architecture by adding either an architecture notation, or an
architecture processing instruction to their document.
The [2]HTML 4.0 specifications force the [3]HTML 4.0 DTD to define
document semantics by stating that authors are not allowed to modify
the document type definition. This restricts authors from adding
logical elements that do not exist in HTML to their document. Authors
cannot add their own entities that they may want to use in their
document. If HTML becomes an SGML architecture, these restrictions can
be removed, and authors will be free to use whatever DTD suits their
documents.
Creating an HTML architecture will facilitate the progress to full
SGML on the web. Once authors create a mapping between the HTML
architectural forms and their document elements, user agents will be
able to read their SGML documents.
Converting HTML to an SGML architecture is easy. Since a set of SGML
architectural forms is almost identical a DTD, the only thing that
needs to be changed is the way that HTML documents are defined.
Currently HTML documents must begin with some variant of the following
line:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0//EN"
"http://www.w3.org/TR/REC-html40/strict.dtd">
Using an SGML architecture, documents would instead be required to
begin with something like the following processing instruction:
<?IS10744:arch
name="HTML 5.0"
public-id="-//W3C//NOTATION HTML 5.0 ARCHITECTURE//EN"
dtd-public-id="-//W3C//DTD HTML 5.0//EN"
doc-elem-form="HTML"
>
Since XML is a subset of SGML, it could also be used to make HTML
documents. The following is an example of an XML HTML document.
<?XML VERSION="1.0"?>
<?IS10744:arch
name="HTML 5.0"
public-id="-//W3C//NOTATION HTML 5.0 ARCHITECTURE//EN"
dtd-public-id="-//W3C//DTD HTML 5.0//EN"
doc-elem-form="HTML"
?>
<HTML LANG="en-CA">
<HEAD>
<TITLE>Short Example</TITLE>
</HEAD>
<BODY>
<P>This is a short example of an HTML document.</P>
</BODY>
</HTML>
The transition to supporting HTML architectures can be made easier by
allowing user agent support to be optional. User agents would only be
required to support those documents which explicitly use the HTML DTD.
This will probably be the most common use of the architecture anyways.
Most authors will validate their documents against the HTML DTD since
it provides enough structure. But the option of using another DTD will
be available to the author. An example of the common use of the HTML
architecture would be the following:
<?IS10744:arch
name="HTML 5.0"
public-id="-//W3C//NOTATION HTML 5.0 ARCHITECTURE//EN"
dtd-public-id="-//W3C//DTD HTML 5.0//EN"
doc-elem-form="HTML"
>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 5.0//EN">
<HTML LANG=en-CA>
<TITLE>Short Example</TITLE>
<P>This is a another short example of an HTML document.
So we see that creating an HTML architecture opens up a world of
flexibility to those authors that want to take advantage of it. It
maintains the structure that some user agents require. It eases the
transition of SGML and XML onto the web. And it is extremely easy to
implement. This is where the future of HTML lies.
Works Cited
C. M. Sperberg-McQueen, Robert F. Goldstein ``HTML to the Max A
Manifesto for Adding SGML Intelligence to the World-Wide Web.''
1994-09-18. 1998-03-15
<URL:[4]http://www.ncsa.uiuc.edu/SDG/IT94/Proceedings/Autools/sperberg
-mcqueen/sperberg.html>
``HTML 4.0 Specification.'' Ed. Dave Raggett et al. 1997-12-18. [5]W3C.
1998-01-23 <URL:[6]http://www.w3.org/TR/REC-html40/>
Kimber, W. Eliot ``A Tutorial Introduction to SGML Architectures.'' 1997.
[7]ISOGEN International Corp. 1998-03-16
<URL:[8]http://www.isogen.com/papers/archintro.html>
Kimber, W. Eliot ``Re: Is XML < SGML? For how long?...'' Online posting.
1998-02-17. [9]comp.text.sgml
<URL:[10]news:34E9CBC9.401B6BB0@isogen.com>
Kimber, W. Eliot ``Re: Is XML < SGML? For how long?...'' Online posting.
1998-02-18. [11]comp.text.sgml
<URL:[12]news:34EB13C0.B7FD0F02@isogen.com>
Newcomb, Steven R. ``SGML Architectures Implications and Opportunities
for Industry.'' [13]<TAG> 1995-08. SGML Associates, Inc. 1998-03-15
<URL:[14]http://tag.sgml.com/08080101.htm>
_________________________________________________________________
[15]Russell O'Connor: [16]roconnor@uwaterloo.ca
References
1. mailto:roconnor@uwaterloo.ca
2. http://www.w3.org/TR/REC-html40/
3. http://www.w3.org/TR/REC-html40/sgml/dtd.html
4. http://www.ncsa.uiuc.edu/SDG/IT94/Proceedings/Autools/sperberg-mcqueen/sperberg.html
5. http://www.w3.org/
6. http://www.w3.org/TR/REC-html40/
7. http://www.isogen.com/
8. http://www.isogen.com/papers/archintro.html
9. news:comp.text.sgml
10. news:34E9CBC9.401B6BB0@isogen.com
11. news:comp.text.sgml
12. news:34EB13C0.B7FD0F02@isogen.com
13. http://tag.sgml.com/
14. http://tag.sgml.com/08080101.htm
15. file://localhost/u3/roconnor/public_html/
16. mailto:roconnor@uwaterloo.ca
--
Russell O'Connor roconnor@uwaterloo.ca
<URL:http://www.undergrad.math.uwaterloo.ca/%7Eroconnor/>
"And truth irreversibly destroys the meaning of its own message"
-- Anindita Dutta, "The Paradox of Truth, the Truth of Entropy"
Received on Friday, 20 March 1998 00:27:21 UTC