On Nov 14, 4:53 am, "Ondrej Certik" <[EMAIL PROTECTED]> wrote: > On Fri, Nov 14, 2008 at 3:21 AM, Brian Granger <[EMAIL PROTECTED]> wrote: > > > I am a sympy newbie, but I do have some thoughts on this issue. I am > > not entirely opposed to the new notation, but I think it may be worth > > considering more... > > > First, the new syntax is confusing two different things: > > > * Substitution syntax > > * Functions and the function call syntax. > > > When I see f(2, 3), I think of evaluating a function, not of > > substitution. I don't have any real concrete evidence to support this > > claim, but the clouding of these two things feels wrong. > > > Second, some versions of the syntax are horribly magic and confusing: > > > f = x*y*w*q > > > While passing things as keyword args is not too magic (and plenty explicit): > > > f(x=1, y=2), > > > passing things by position is a nightmare. What on earth do the > > following actually mean: > > > f(1) > > f(1,2) > > f(1,2,3) > > > The only way of resolving this is to agree upon some magic ordering of > > symbol/atom names, which is, in my mind, way too implicit and magical. > > Sure maybe it is nice to 1 or two arguments, but the general case is > > pretty nasty. > > > The only way that I can imagine supporting the positional version is > > something like this: > > > f.bind_positional_arguments(x, y) # we could find a shorter name of course > > f(1,2) -> f(x=2,y=3) > > > f.positional_arguments would return (x, y) > > > So, I would say that I am: > > > +1 on the keyword argument version f(x=1, y=2) > > -1 on the raw positional version f(1,2) > > +1 on a more explicit version of the positional version > > I agree with this. Let's implement > > the keyword argument version f(x=1, y=2) > a more explicit version of the positional version > > first, and then see.
> Ondrej There has been some pain in Sage due to symbolic expressions there allowing to be called with positional arguments. Have a look, especially towards the end, at the long thread http://groups.google.com/group/sage-devel/browse_thread/thread/f1286e92d4d2ce83#. I think the conclusion, at least by some, was similar to yours, and I also agree. The keyword version is good, and the positional version is bad. Jason Merrill --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to sympy@googlegroups.com To unsubscribe from this group, send email to [EMAIL PROTECTED] For more options, visit this group at http://groups.google.com/group/sympy?hl=en -~----------~----~----~----~------~----~------~--~---
