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Case Folding (was: XHTML/XML comment)

From: Arjun Ray <aray@q2.net>
Date: Mon, 31 Jan 2000 17:46:54 -0500 (EST)
To: www-html@w3.org
Message-ID: <Pine.LNX.4.10.10001311736120.15214-100000@mail.q2.net>


On Mon, 31 Jan 2000, Frank Boumphrey wrote:

> this 'correct' explanation also demonstrates why XML was
> introduced to simplify the grammar of SGML :>)

Well, in my experience the main trouble with SGML has been the
inaccesibility of authoritative materials.  As a result, much of what
gets commonly known or said about SGML is runor, hearsay, old wives
tales, just-so stories, and so on.  'Case insensitive' is just another
convenient oversimplification - correct to casual appearance, thus
plausible enough to be misimplemented, and the cause of unnecessary
grief down the road.  There's nothin intrinsically difficult about the
correct concept - case folding - is there?

Just for kicks, you could try this:  modify the SGML declaration that
nsgmls uses on your system (assuming case folding is enabled) to add a
character each to the LCNMCHAR and UCNMCHAR classes, e.g. change

    LCNMCHAR  ".-_:"
    UCNMCHAR  ".-_:"

to

    LCNMCHAR  ".-_:^"
    LCNMCHAR  ".-_:@"

Now look at this:

[test]$ cat foo.sgm
<!DOCTYPE foo [
  <!ELEMENT foo - - (#PCDATA) >
   <!ATTLIST foo bar^  CDATA #FIXED 'baz' >
]>
<foo>blah</foo>
[test]$ nsgmls foo.sgm
ABAR@ CDATA baz
(FOO
-blah
)FOO
C
[aray@devel xhtml11]$
[test]$


Note the last character in the name of the attribute:)



Arjun



   
Received on Monday, 31 January 2000 17:34:24 GMT

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