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Re: a question about <forall> element

From: Stan Devitt <jsdevitt@stratumtek.com>
Date: Tue, 08 Jul 2003 13:22:06 -0400
Message-ID: <3F0AFDBE.2070500@stratumtek.com>
To: www-math@w3.org


     I am working my way through your messages in detail to make sure we 
have at least considered everything.  You will be getting several 
messages from me over the next while summarizing the outcome of our review.

Once again, a response from you acknowledging that your points have at 
least been considered will help us to close out the issues list.   One 
response to each message will be fine.

Stan Devitt
Math Working Group

 > Re: a question about <forall> element
 > From: Andreas Strotmann (Strotmann@rrz.uni-koeln.de)
 > Date: Tue, May 06 2003
 >Message-ID: <3EB7DBBC.7020709@rrz.uni-koeln.de>
 >Date: Tue, 06 May 2003 17:58:52 +0200
 >From: Andreas Strotmann <Strotmann@rrz.uni-koeln.de>
 >To: Robert Miner <RobertM@dessci.com>
 >CC: www-math@w3.org
 >Subject: Re: a question about <forall> element
 >I stand corrected then, Robert.
 >However, it does say "should", not "must", so any content element is OK,
 >sort of, except reln, which is explicitly depracated. You may have to
 >fix the validation grammar then (though it should issue a warning, I
The validation grammar has been fixed to make the treatment of these
and other operators more regular and to allow more general arguments. 
As a result, some uses that were arbitrarily restricted before either
in the wording or the grammar now are allowed.
 >Still, the original poster appears to have hit upon a serious problem
 >here.  I can't think of a single case where insisting on a specific type
 >of argument would be OK in all cases.  In this particular case, just
 >replace the body, variable x, with a logical constant such as true or
 >false, and you have a perfectly sensible mathematical statement that
 >should be representable in a straight-forward way without inserting an
 >identity function into it somehow.
In fixing the grammar, we have taken into account that this was a 
general problem and the arity requirements have been relaxed.  The 
primary change in the grammar has been that it now treats most of
the operators that could sensibly be n-ary as n-ary and also allows
use of domain of application in all its various forms.

The old usage is of course still valid.

 >This reminds me of a problem that I posted a long, long time ago, about
 >having interval both as a constructor and as a qualifier element.
 > That's a dangerous syntactic ambiguity: is an apply with an integral
 >operator and an interval element a) an operator on functions which
 >returns the integral of an argument function over that interval, or b)
 >the indefinite integral of an interval-valued function?

Interval may still be a qualifier, but the possible ambiguity has been 
addressed.  In the ordinary course of events, when used in an apply 
where a qualifier is expected then it is a qualifier.  If anything 
occurs (such as multiple occurrences of an interval) to put this 
interpretation in doubt then they must be interreted as an ordinary 

Editorial Note:  Issues 12-1 to 12-3
Received on Tuesday, 8 July 2003 13:19:54 UTC

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