On 25 August 2011 10:33, Mathias Gaunard <mathias.gaunard@ens-lyon.org> wrote:
On 25/08/2011 01:18, Daniel James wrote:
On 24 August 2011 23:11, Mathias Gaunard<mathias.gaunard@ens-lyon.org> wrote:
On 08/24/2011 06:55 PM, Dave Abrahams wrote:
That's an asymmetry about most currying syntax that I never liked, at least for C++. I suppose when all functions are fully lazy there's no assymmetry, but that's not C++. In C++ we have parens to trigger evaluation. Even in Phoenix, laziness only goes partway: you still need parens to trigger final evaluation.
ML-based languages are not lazy and have had currying for 40 years. Yet the academics behind functional programming, lambda calculus, theorem proving and logic still seem to fancy them a lot.
But ML doesn't have C++ style overloading. Currying certain overloaded functions is ambiguous.
Which is why I suggested only applying currying to monomorphic functions.
But that's not much good for C++. Explicitly specifying the number of arguments is a bit better, but then the situations where that can do something that bind can't are quite rare. I think explicit partial function calls would be a better fit for C++, i.e. std::transform(begin(), end, inserter, partial(std::plus<int>(), 10)); It would be clear when you're explicitly calling the function, and when you're not. And the implementation would be considerably simpler. It could support placeholders if you don't like simplicity. I think an 'uncurry' is also possible, I'm not sure how useful it would be.