Subject: Re: [boost] Does boost help in creating generic function wrappers?
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2010-07-14 22:55:44
AMDG
Andy Venikov wrote:
> In c++0x, creating a generic function wrapper is a bliss:
>
> template <typename Func>
> class gen_wrapper
> {
> Func && func_;
> public:
> gen_wrapper(Func && in) : func_(in) {}
>
> template <typename ... Prms>
> /*deduce result here */
> operator() (Prms && ... prms)
> {
> //Do something special here.
> //NOTE: we can operate with arguments here too
>
> return func_(std::forward<Prms>(prms)...);
> }
>
> };
>
> That's it.
>
> But if I don't have C++0x, can boost help here?
>
> functional/forward_adapter won't work since it hides function
> parameters, it only lets you operate with the function.
What do you mean by "hides function parameters"?
> It looks like it may be possible to do that by using boost/preprocessor
> I'll have to generate a whole lot of overloads with O(2^N) (because of
> the overload on (T &) or (T const &) for every argument).
> But it looks pretty dounting. It's basically what forward_adapter had
> to do.
>
> Isn't there a ready-made library that would allow me to generate all
> of the overloads?
Just define your wrapper to take references, and wrap it in forward_adapter.
This should have exactly the same effect as defining all the overloads
yourself.
In Christ,
Steven Watanabe