[C++-sig] Possible overload<> template for class members

[Joel de Guzman]

----- Original Message ----- 
From: "Joel de Guzman" <djowel at gmx.co.uk>

> ----- Original Message ----- 
> From: "Aleksey Gurtovoy" <agurtovoy at meta-comm.com>
> 
> 
> > Ralf W. Grosse-Kunstleve wrote:
> > > --- William Trenker <wtrenker at hotmail.com> wrote:
> > > > .def("show", overload<void,void>(), &Window::show)
> > > > .def("show", overload<void,const Window*>(), &Window.show)
> > > 
> > > That looks just like my old "plan A" :-)
> > > 
> > > >   Is something like this even possible?
> > > 
> > > David kept claiming the answer is no, because in C++ you cannot take
> > > the "address" of a family over overloaded functions. If Window.show 
> > > has overloads the compiler has no way of knowing which one you mean 
> > > if you just type &Window.show.
> > 
> > Hmm, seems entirely possible to me:
> > 
> [snip]
> > 
> > Am I missing something?
> 
> Cool Aleksey, cool! I think your scheme will work, AFAICT.
> Might need some workarounds on VC6 and CW7.2.
> Compiles on g++2.95, g++3.1, Comeau, intel and VC7.
> 
> However, it still can't handle default arguments automatically :-(
> For instance:
> 
>     void show(int = 45, bool* = 0, char 'x') {}
> 
> I still see no way to def this in one fell swoop. You still need
> three defs.
> 
> ... Or am I missing something?

Furthermore, you can't def overloads with common arguments
automatically in one shot:

    void show() {}
    void show(int) {}
    void show(int, bool*) {}
    void show(int, bool*, char) {}

Oh well....

Anyway, it seems better than having to cast the function pointer
for overloads.

Cheers,
Joel de Guzman
joel at boost-consulting.com
http://www.boost-consulting.com