let ::boost:: adaptors:: transformed accept raw function pointers too

[giecrilj@…]

#include <cstdlib>
#include <vector>
#include <boost/range/algorithm/find.hpp>
#include <boost/range/adaptor/transformed.hpp>
#include <boost/mem_fn.hpp>

class X { public: int foo () const; };

#define MEM_FN 
#ifndef MEM_FN
#define MEM_FN ::boost:: mem_fn 
#endif

int main () 
{ 
  ::boost:: find
    (::std:: vector < X > () 
     | ::boost:: adaptors:: transformed (MEM_FN (&X:: foo)), 0); 
return +EXIT_SUCCESS; }

/usr/include/boost/iterator/transform_iterator.hpp:42:47: error: ‘int (X::*)()const’ is not a class, struct, or union type

[Neil Groves]

There is an easier solution that already works. If you just use boost::bind(&X::foo, _1) instead of the MEM_FN macro it works. This also works everywhere else in Boost.Range it accepts a functor without requiring a combinatorial explosion of function overloads.