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Re: A note on case sensitivity



> From: Martin Bryan <mtbryan@sgml.u-net.com>
> 
> At 12:58 AM 25/10/96 EDT, lee@sq.com wrote:
> 
> >Case insensitivity . . .
>
> I feel that the advantages
> that XML could offer by providing for a full range of 10646 characters
> for naming, etc, more than outway the disadvantage of having to be case
> sensitive in element and attribute names, etc.
> 
> . . .

Make mine a vote against NAMECASE GENERAL NO.  In fact, I would say
that XML should allow only NAMECASE GENERAL YES.  Much as I'm used
to case sensitivity (e.g., on Unix), I think we'll be stepping into
all sorts of problems with NAMECASE GENERAL NO.

There are many tools out there that assume case insensitivity of
element and attribute names as well as NAME-type attribute value
tokens.  Just stop and think of all the DTDs out there that use
the lowercase "o" in the omitted tag minimization field of an
element declaration--this won't parse with NAMECASE GENERAL NO
in force.  I bet a fair number of the style sheet processors out
there that will find they run into subtle problems with NAMECASE
GENERAL NO.  And most SGML users will be very surprised with
case sensitivity of element and attribute names.

If we want to define XML so that it doesn't work with existing
tools and doesn't work with existing DTDs and document instances
and doesn't benefit from the knowledge base of the existing SGML
users, then we can consider making elements, attributes, and
name tokens in attribute values case sensitive.  Case sensitivity
in and of itself isn't bad.  But given the context in which XML
is being born, I'd recommend against NAMECASE GENERAL NO at least
for XML 1.0.