// Really dumb iterator_adaptor example program  -----------------------------//

// (C) Copyright Beman Dawes 2002. Permission to copy, use, modify, sell and
// distribute this software is granted provided this copyright notice appears
// in all copies. This software is provided "as is" without express or implied
// warranty, and with no claim as to its suitability for any purpose.

#include <boost/iterator_adaptors.hpp>
#include <string>
#include <iostream>

class my_base
{
public:
  std::string name;
  my_base() : name( "foo" ) {}
  void operator++() { name = "bar"; }
  bool operator==( const my_base & rhs ) const { return name == rhs.name; }
};

// if my_base had "const std::string & operator*() const { return name; }"
// then custom policies would not be required.
class my_policies : public boost::default_iterator_policies
{
public:
  template <class IteratorAdaptor>
  typename IteratorAdaptor::reference dereference(const IteratorAdaptor& x) const
    { return x.base().name; }
};

typedef boost::iterator_adaptor<
  my_base,
  my_policies,  // default_iterator_policies would do if my_base::op* were present
  const std::string,
  const std::string &,
  const std::string *,
  std::forward_iterator_tag,
  std::string::difference_type > my_iterator;

int main()
{
  my_iterator itr;
  my_iterator::value_type str( "hello, iterator\n" ); //verify value_type present
  std::cout << str;
  std::cout << *itr << std::endl;   // foo
  std::cout << *++itr << std::endl; // bar
  std::cout << (itr == my_iterator() ? "bingo!" : "oops!" ) << std::endl; // oops
  std::cout << (itr == ++my_iterator() ? "bingo!" : "oops!" ) << std::endl; // bingo
  return 0;
}