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/**
* \file main.cpp
* \brief Sample program presenting the use of the claw::memory namespace.
* \author Julien Jorge
*/
#include <claw/smart_ptr.hpp>
#include <string>
#include <sstream>
#include <iostream>
#include <list>
/*----------------------------------------------------------------------------*/
/**
* \brief Simple class, containing a string message. To illustrate the use of
* claw::memory.
*/
class message
{
public:
message( const std::string& msg )
: m_msg(msg)
{ }
~message()
{
std::cout << "deleting " << m_msg << std::endl;
}
const std::string& get_message() const { return m_msg; }
private:
std::string m_msg;
}; // class message
/*----------------------------------------------------------------------------*/
/**
* \brief Chained structure to show the problems occuring with the use of
* references count.
*/
struct item
{
claw::memory::smart_ptr<item> next;
}; // struct item
/*----------------------------------------------------------------------------*/
/**
* \brief Print a \a message stored in a smart_ptr. The parameter is passed by
* copy.
*/
void print_copy( claw::memory::smart_ptr<message> p )
{
std::cout << "print_copy" << std::endl;
std::cout << " (->) " << p->get_message() << std::endl;
std::cout << " (*) " << (*p).get_message() << std::endl;
} // print_copy()
/*----------------------------------------------------------------------------*/
/**
* \brief Print a \a message stored in a smart_ptr. The parameter is passed by
* reference.
*/
void print_ref( claw::memory::smart_ptr<message>& p )
{
std::cout << "print_ref" << std::endl;
std::cout << " (->) " << p->get_message() << std::endl;
std::cout << " (*) " << (*p).get_message() << std::endl;
} // print_ref()
/*----------------------------------------------------------------------------*/
/**
* \brief Print a \a message stored in a smart_ptr. The parameter is passed by
* reference (to test the constant methods of smart_ptr).
*/
void print_const( const claw::memory::smart_ptr<message>& p )
{
std::cout << "print_const" << std::endl;
std::cout << " (->) " << p->get_message() << std::endl;
std::cout << " (*) " << (*p).get_message() << std::endl;
} // print_const()
/*----------------------------------------------------------------------------*/
/**
* \brief Create some smart_ptr, call print_*() methods and do some operations.
*/
void basic_test()
{
std::cout << "----------------- basic_test" << std::endl;
claw::memory::smart_ptr<message> p = new message( "basic_1" );
claw::memory::smart_ptr<message> q = new message( "basic_2" );
claw::memory::smart_ptr<message> p2(p);
claw::memory::smart_ptr<message> q2;
claw::memory::smart_ptr<message> r( NULL );
print_copy(p);
print_ref(p);
print_const(p);
std::cout << "instruction: p = p = p" << std::endl;
p = p = p;
std::cout << "instruction: q2 = q" << std::endl;
q2 = q;
} // basic_test()
/*----------------------------------------------------------------------------*/
/**
* \brief Use a smart_ptr with a class from the STL.
*/
void stl_test()
{
std::cout << "----------------- stl_test" << std::endl;
std::list< claw::memory::smart_ptr<message> > list;
std::list< claw::memory::smart_ptr<message> >::const_iterator it;
for ( unsigned int i=0; i!=10; ++i )
{
std::ostringstream oss;
oss << i;
list.push_back( new message(oss.str()) );
}
for ( it=list.begin(); it!=list.end(); ++it )
std::cout << (*it)->get_message();
std::cout << std::endl;
} // stl_test()
/*----------------------------------------------------------------------------*/
/**
* \brief Example of the problems occuring with the use of references count.
*/
void loop_test()
{
std::cout << "----------------- loop_test" << std::endl;
claw::memory::smart_ptr<item> i1 = new item;
claw::memory::smart_ptr<item> i2 = new item;
i2->next = i1;
i1->next = i2;
} // test_boucle()
/*----------------------------------------------------------------------------*/
/**
* \brief Main program. Call test methods.
*/
int main()
{
basic_test();
stl_test();
loop_test();
return 0;
} // main()
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