Date: Fri, 20 Mar 1998 00:25:43 -0500 (EST) From: "Russell Steven Shawn O'Connor" <email@example.com> To: firstname.lastname@example.org Message-ID: <Pine.SOL.3.95q.980320002353.28598Aemail@example.com> Subject: Future of HTML Future of HTML File location: <URL:http://www.undergrad.math.uwaterloo.ca/%7Eroconnor/HtmlArch.html> Proposer contact: firstname.lastname@example.org Name: Russell O'Connor Tel: 204-753-2440 _________________________________________________________________ HTML Architecture By: 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 HTML 4.0 specifications force the 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: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. W3C. 1998-01-23 <URL:http://www.w3.org/TR/REC-html40/> Kimber, W. Eliot ``A Tutorial Introduction to SGML Architectures.'' 1997. ISOGEN International Corp. 1998-03-16 <URL:http://www.isogen.com/papers/archintro.html> Kimber, W. Eliot ``Re: Is XML < SGML? For how long?...'' Online posting. 1998-02-17. comp.text.sgml <URL:news:34E9CBC9.401B6BB0@isogen.com> Kimber, W. Eliot ``Re: Is XML < SGML? For how long?...'' Online posting. 1998-02-18. comp.text.sgml <URL:news:34EB13C0.B7FD0F02@isogen.com> Newcomb, Steven R. ``SGML Architectures Implications and Opportunities for Industry.'' <TAG> 1995-08. SGML Associates, Inc. 1998-03-15 <URL:http://tag.sgml.com/08080101.htm> _________________________________________________________________ Russell O'Connor: email@example.com References 1. mailto:firstname.lastname@example.org 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:email@example.com -- Russell O'Connor firstname.lastname@example.org <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"