[Om3] Being pragmatic about the semantics of, eg, variables and functions

[Professor James Davenport]

On Tue, March 24, 2009 3:01 pm, Robert Miner wrote:
> I'm not sure we are talking about the same proposals.  You mention adding
> a condition child to OMBIND, and while that has been mentioned by several
> people, I don't think there is a concrete proposal spelling out the
I think the (full) D/K paper is such a proposal, but it's only a proposal,
and many are against it.
> details of that.  From the MathML point of view, I think that would amount
> to allowing <condition> in strict markup.  To me, that pushes off the
Not quite. To me, it allows <condition> in strict markup WHERE the CDs
permit such a binding operator. Now, this pushes work off to the CDs, and
if MathML is such that that means <condition> is allowed anywhere in
strict markup since CD verification is optional (I just don't know) I can
understand more objections to that.
> problem to the future, and allows OM to specify the mapping to OM3 later.
>
> I'm okay with that, since it decouples the OM3 work from the MML3 work.
See below.

> It isn't the OM -> XXX direction that is hard.  It is the pragmatic ->
> strict mapping that is hard.
I understand that,

> I think you are talking about OM here.  From my MathML viewpoint, there
> isn't a problem with readability or writability: use pragmatic markup.
> The problem is algorithmically mapping it to strict markup, for which I
> don't think readability or writability is very important -- pragmatic
> markup is already the solution to that problem.
? unless roundtripping via strict/OM makes the readable unreadable.
>
> To summarize, my main interest at this point is decoupling the work on
> MathML 3 from the resolution of this OM3 debate.  I really think we have
> to finish Chapter 4 in a matter of weeks -- completely -- and I just can't
> see how to do that, as long as filling out the strict markup for the
> remaining operators and examples in 4.4 depends on the conclusion of the
> OM3 binder debate.  Thus, the argument I'm making is that the only
> feasible thing to do for MathML 3 is to carry on using the current text
> (which essentially makes strict CMML isomorphic to OM2).  That allows me
> to reuse more exposition from MML2, it allows us to stick with the
> examples and strict equivalents David already produced, and so on.
I understand the need to get finished, and there are moments when the
perfect is the enemy of the good. as I see it, this would leave:
(*) "Rule 2" --- "Note that the order of bound variables..." (4.2.3.2 of
MML2) in place as the means of tying up the x in the integrand with the x
(or whatever) in the domain;
(*) An issue with uplimit/lowlimit versus intervals in int.
If I'm right on the second, I'll come back with a proposal on it.

As for the first, am I right in the following:
(a) This wouldn't preclude OM developing intcond etc. later;
(b) Since Strict will be isomorphic to OM, these will therefore be part of
strict;
(c) Therefore pragmatic->strict COULD be (pace David, I won't say WOULD)
be enhanced to use these in the future?
If I am right here, then we probably have a way forward that works today
and doesn't preclude growth tomorrow.

James Davenport
Visiting Full Professor, University of Waterloo
Otherwise:
Hebron & Medlock Professor of Information Technology and
Chairman, Powerful Computing WP, University of Bath
OpenMath Content Dictionary Editor and Programme Chair, OpenMath 2009
IMU Committee on Electronic Information and Communication