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Re: a question about <forall> element

From: Andreas Strotmann <Strotmann@rrz.uni-koeln.de>
Date: Wed, 09 Jul 2003 13:03:16 +0200
Message-ID: <3F0BF674.7020903@rrz.uni-koeln.de>
To: Stan Devitt <jsdevitt@stratumtek.com>
CC: www-math@w3.org


I'm quite happy with the resolution you describe below. 

Even though it's probably not easy to formalize your resolution of the 
<interval> ambiguity, at this stage an intentional bit of vagueness may 
be the better approach compared with a prematurely formalized solution.

-- Andreas

Stan Devitt wrote:

> Andreas,
>     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
> >suppose).
> >
> [Stan]
> 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.
> >
> [Stan]
> 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?
> >
> [Stan]
> 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 
> operands.
> ===============
> Editorial Note:  Issues 12-1 to 12-3
Received on Wednesday, 9 July 2003 07:03:24 UTC

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