Chris > And moreover, there is no difference between these since 'being an element > of the domain' is a condition; and the other conditions are merely 'AND'ed > with this condition to describe a new domain.
Yes this is exactly my objection to prodcond, prod already takes a domain, so prodcond which takes a domain and a condition, is totally unnecessary. > So it comes back to the question of how close to commonly used non-digital > methods of describing 'mathematical semantics' should OM be? I think I got as far as Phd level of education in mathematics without ever being shown or thinking about explict binding operations. (Of course you are aware that certain variable in certain constructions bind, but never viewed binding itself as an explict construct in the sense of the lambda calculus. I only met the (typed and untyped) lambda calculus later, when I deserted my former colleagues and ended up in a Computer Science department... So while it's fun (and perhaps even useful) to argue the merits of typed versus untyped foundational systems as being the correct basis for Openmath, I don't really believe that any system that models mathematical functions as the kind of formal term expression implied by OM or MathML or any kind of lambda calculus is ever going to look particularly natural to the man in the street (or even the mathematics common room). Most people (XML geeks excepted) would say that any encoding using XML looks pretty unnatural anyway. So I don't think this is really a problem in practice, so long as there is a well defined mechanism to go from what is meant to what must be encoded in OpenMath, adding a few suchthat and lambda symbols at the same time as adding the XML markup is just "stuff" which needs to be done but shouldn't affect the way you think or talk about or teach the original expression. David ________________________________________________________________________ The Numerical Algorithms Group Ltd is a company registered in England and Wales with company number 1249803. The registered office is: Wilkinson House, Jordan Hill Road, Oxford OX2 8DR, United Kingdom. This e-mail has been scanned for all viruses by Star. The service is powered by MessageLabs. ________________________________________________________________________ _______________________________________________ Om3 mailing list [email protected] http://openmath.org/mailman/listinfo/om3
