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// An example of defining a postconstructor for a class which
// uses boost::signals2::deconstruct as its factory function.
// This example expands on the basic postconstructor_ex1.cpp example
// by passing arguments to the constructor and postconstructor.
// Copyright Frank Mori Hess 2009.

// Use, modification and
// distribution is subject to the Boost Software License, Version
// 1.0. (See accompanying file LICENSE_1_0.txt or copy at
// For more information, see

#include <boost/shared_ptr.hpp>
#include <boost/signals2/deconstruct.hpp>
#include <iostream>
#include <sstream>
#include <string>

namespace bs2 = boost::signals2;

namespace mynamespace
  class Y
    /* This adl_postconstruct function will be found
    via argument-dependent lookup when using boost::signals2::deconstruct. */
    template<typename T> friend
      void adl_postconstruct(const boost::shared_ptr<T> &, Y *y, const std::string &text)
      y->_text_stream << text;
    void print() const
      std::cout << _text_stream.str() << std::endl;
    friend class bs2::deconstruct_access;  // give boost::signals2::deconstruct access to private constructor
    // private constructor forces use of boost::signals2::deconstruct to create objects.
    Y(const std::string &text)
      _text_stream << text;

    std::ostringstream _text_stream;

int main()
  boost::shared_ptr<mynamespace::Y> y = bs2::deconstruct<mynamespace::Y>("Hello, ").postconstruct("world!");
  return 0;