programming, using op(), was ..RE: Bugfix for GosperSum? (was: cannot load Zeilberger)

> I vote for something like
>
> case(expr,
>        "+", xxx,
>        "*", yyy,
>        otherwise, zzz)
>
> There are other situations in Maxima ('depends', for example) where the
> meaning of an argument depends on its position in the arguments list.

Yes, and that's confusing, isn't it, because in a long list ..., a, b, c, ...
that might be interpreted as (a, b), (c, ...) or as (..., a), (b, c).
Various declaration functions have this misfeature; that's a bad
precedent I don't want to propagate.

All the best,
Robert