Re: What are the problems with IDML? (fwd)

Murray Altheim (murray@spyglass.com)
Fri, 23 Aug 1996 14:11:14 -0500


Message-Id: <v02110115ae43adfb6617@[140.186.34.50]>
Date: Fri, 23 Aug 1996 14:11:14 -0500
To: donohoe@emerge.com
From: murray@spyglass.com (Murray Altheim)
Subject: Re: What are the problems with IDML? (fwd)
Cc: www-html@w3.org

Doug Donohoe <donohoe@emerge.com> writes:
>Murray Altheim wrote:
>>
>> I think you'll probably see this under a separate message, but I am rather
>> baffled as to how you COULD use META in place of IDML tags within BODY.
>>
>
>This may be a stupid question but....
>
>If I put META in the body of my HTML document, neither Netscape
>nor IE choke (they seem quite complacent about it, as a matter of
>fact).  So, what exactly _does_ break when I put
>META inside the BODY?  If 99% of HTML is viewed through these
>two browsers, who cares if I put META in the "wrong" place?
>I know SGML or HTML parsers will complain, but what does
>it break in the real world?  E.g., what problems does it cause?

You can put a whole lot of things in most browsers and they don't choke.
Browsers are designed to handle extremely egregrious errors without
choking. Our QA department lets us know when they find a document that
actually bombs the browser, or causes severe problems (and we have seen
some UGLEEE documents).  Unknown tags should be ignored by UAs (User
Agents: browsers, search engines, etc.), a behavior called an "application
convention" defined in the HTML proposed standard [IETF RFC 1866]. This is
why it's not a good idea to use a browser to "validate" your document.

The issue here comes from the purpose of valid markup. Markup is different
than raw content -- it has rules. Where James Joyce could break all the
rules in writing Finnigan's Wake, markup should conform to its definition,
otherwise there can be no guarantee of either correct or complete
presentation. In other words, a marked-up version of Finnigan's Wake that
had markup errors might not display it correctly (and who'd notice?). Same
thing with an online bank financial statement: what if part of it were
missing?

META is an element restricted to the HEAD of a document. Putting it
elsewhere won't "break" Netscape, but your document no longer conforms to
any existing markup definition for HTML (ie., HTML Document Type
Definition, or DTD).

The correct solution for your perceived need was what you did: create
elements to support the need. All you need now is a DTD to define those
elements, and you can then validate your documents (using an SGML tool like
[nsgmls]) against that DTD to be sure that the markup is valid and that
your document content can be processed by tools that understand that markup
(like a search engine trained to understand IDML).

>I'm not an SGML expert, so please be patient if I've asked
>an obvious question.  Thanks,

There seems to be little understanding of META in general in this list, so
it is apparently NOT an obvious question to some.

Murray

[IETF RFC 1866] Hypertext Markup Language - 2.0
    ftp://cs.internic.net/rfc/rfc1866.txt

[nsgmls] is part of the SP SGML package by James Clark
    http://www.jclark.com/

```````````````````````````````````````````````````````````````````````````````
     Murray Altheim, Program Manager
     Spyglass, Inc., Cambridge, Massachusetts
     email: <mailto:murray@spyglass.com>
     http:  <http://www.stonehand.com/murray/murray.html>
            "Give a monkey the tools and he'll eventually build a typewriter."