No Such Blog or Diary

#include <iostream>
 
struct h {};
struct k : h {};
 
namespace g {
  inline bool f(...) { return false; }
  inline bool f(h* ) { return true;  }
}
namespace v {
  template <typename A>
  inline bool f(A)   { return false; }
  inline bool f(h* ) { return true;  }
}
 
int main(int argc, char *argv[])
{
  h *ph; k *pk; int *pi;
  std::cout << g::f(pi) << std::endl;
  std::cout << g::f(ph) << std::endl;
  std::cout << g::f(pk) << std::endl;
  std::cout << v::f(pi) << std::endl;
  std::cout << v::f(ph) << std::endl;
  std::cout << v::f(pk) << std::endl;
}

#include <iostream>
#include <boost/function.hpp>
 
struct F_t {
  double operator()(const double & x) const { return 1.5 * x; }
} F;
 
inline double G(const double & x) { return 1.5 * x; }
 
int main(int argc, char *argv[])
{
  boost::function <double(const double &)> f = F;
  boost::function <double(const double &)> g = G;
  std::cout << f(2.0) << std::endl;
  std::cout << g(2.0) << std::endl;
}