🚀 go-pugleaf

Why doesn't STL have a pointer to member function adaptor, such as:

template <class Arg1, class Arg2, class Result>
class pointer_to_member_function : public binary_function<Arg1,Arg2,Result>
{
  public:
    explicit pointer_to_binary_function(Result (Arg1::*f)(Arg2)) : f(f)
      {}

    Result operator()(const Arg1& x, const Arg2& y) const
      { return x.*pf(y); }
};

template <class Arg1, class Arg2, class Result>
pointer_to_member_function<Arg1,Arg2,Result> ptr_fun(Result (Arg1::*f)(Arg2))
{
  pointer_to_member_function<Arg1,Arg2,Result>(f);
}

Of course, there also could a pointer_to_unary_member_function, and a
pointer_to_void_member_function.

IMHO, this seems to be a very easy addition, as well as VERY useful
when you want to use anything in <algorithm>.  [I have wanted it many
times, and after adding it myself, I use it all the time.]

Brian Freyburger


---
[ comp.std.c++ is moderated.  Submission address: std-c++@ncar.ucar.edu.
  Contact address: std-c++-request@ncar.ucar.edu.  The moderation policy
  is summarized in http://dogbert.lbl.gov/~matt/std-c++/policy.html. ]