text: 
  //          Copyright Oliver Kowalke 2009.
  // Distributed under the Boost Software License, Version 1.0.
  //    (See accompanying file LICENSE_1_0.txt or copy at
  //          http://www.boost.org/LICENSE_1_0.txt)
  
  #include <cstdlib>
  #include <iostream>
  
  #include <boost/bind.hpp>
  #include <boost/coroutine/all.hpp>
  
  typedef boost::coroutines::asymmetric_coroutine< void >::pull_type pull_coro_t;
  typedef boost::coroutines::asymmetric_coroutine< void >::push_type push_coro_t;
  
  void echo( pull_coro_t & source, int i)
  {
      std::cout << i;
      source();
  }
  
  void runit( push_coro_t & sink1)
  {
      std::cout << "started! ";
      for ( int i = 0; i < 10; ++i)
      {
          push_coro_t sink2( boost::bind( echo, _1, i) );
          while ( sink2)
              sink2();
          sink1();
      }
  }
  
  int main( int argc, char * argv[])
  {
      {
          pull_coro_t source( runit);
          while ( source) {
              std::cout << "-";
              source();
          }
      }
  
      std::cout << "\nDone" << std::endl;
  
      return EXIT_SUCCESS;
  }
  