AMDG On 5/6/25 4:52 PM, Jean-Louis Leroy via Boost wrote:
Hi Steven,
I tried since you last suggested this. Couldn't make it work. The macro generates something like:
auto poke(std::ostream& a, virtual_ptr<Animal> b) -> void { method<poke_method(std::ostream& a, virtual_ptr<Animal> b)>::fn(a, b); }
There is no way to peel off the `void` from the signature with the syntax you suggest.
It doesn't need to be peeled off by the macro. You're only using it as a template parameter, so you can just pass the whole signature as a function type.
What about the `void` after the arrow?
You mean like this? BOOST_OPENMETHOD(poke, (std::ostream& a, virtual_ptr<Animal> b) -> void) That's possible. You can get a function type by prepending auto, which can be used for most template parameters and (with some metaprogramming) the return type.
It might work if we could define a function using a function type:
using Signature = void(std::ostream& a, virtual_ptr<Animal> b);
Signature poke { method<poke_method(std::ostream& a, virtual_ptr<Animal> b)>::fn(a, b); }
Alas this is illegal. Not sure why. Probably because of the parameter names...
Right. The function type trick works for everything except the actual function definition (where you need the parameter names).
For what it's worth, here is the syntax that I would like:
BOOST_OPENMETHOD(void poke(std::ostream&,virtual_ptr<Animal>)) { ... }
Would be nice. Too bad it that leaves no way to get poke as a usable identifier. In Christ, Steven Watanabe