// Boost shared_ptr_example2 implementation file -----------------------------// #include "shared_ptr_example2.hpp" #include class example::implementation { public: ~implementation() { std::cout << "destroying implementation\n"; } }; example::example() : _imp( new implementation ) {} example::example( const example & s ) : _imp( s._imp ) {} example & example::operator=( const example & s ) { _imp = s._imp; return *this; } void example::do_something() { std::cout << "use_count() is " << _imp.use_count() << "\n"; }