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#include <iostream>
#include <vector>
#include <typeinfo>
using namespace std;
// waarom werkt clone() in de CC niet? Omdat bij de vector's
// push_back(Derived1()) de CC wordt aangeroepen, en niet other.clone(),
// terwijl 't niet duidelijk is hoe
// je in de CC clone() kunt gebruiken. *this = *other->clone() werkt
// niet.
class Base
{
public:
Base()
{
cout << "Base() " << ++s_n << "\n";
}
virtual ~Base()
{
std::cout << "~Base() << s_n--\n";
}
Base(Base const &other)
{
std::cout << "Base(Base const &)\n";
}
virtual Base *clone() const
{
std::cout << "Base clone()\n";
return new Base();
}
};
class Derived1: public Base
{
public:
Derived1()
{
std::cout << "Derived1()\n";
}
Derived1(Derived1 const &other)
{
std::cout << "Derived1(Derived1)\n";
}
~Derived1()
{
std::cout << "~Derived1()\n";
}
virtual Base *clone() const
{
std::cout << "Derived1::clone()\n";
return new Derived1(*this);
}
};
class BWrap
{
Base *d_bp;
public:
BWrap()
:
d_bp(new Base())
{}
BWrap(Base const &bp)
:
d_bp(bp.clone())
{}
BWrap(Base const *bp)
:
d_bp(bp->clone())
{}
~BWrap()
{
destroy();
}
BWrap(BWrap const &other)
{
copy(other);
}
BWrap &operator=(BWrap const &other)
{
if (this != &other)
{
destroy();
copy(other);
}
return *this;
}
Base &base() const
{
return *d_bp;
}
private:
void destroy()
{
delete d_bp;
}
void copy(BWrap const &other)
{
d_bp = other.d_bp->clone();
}
};
int main()
{
vector<Base> bv(1);
cout << "==\n";
Derived1 d1;
cout << "==\n";
bv.push_back(d1);
cout << "==\n";
/*
vector<BWrap> vb;
cout << "==\n";
vb.push_back(Derived1());
cout << "==\n";
vector<BWrap> vb2(vb);
cout << "==\n";
/ *
Derived1 d1;
vb.push_back(d1);
cout << "==\n";
Derived1 dp = &vb[0].ref();
cout << dp << endl;
cout << "==\n";
vb[0] = Base();
cout << "==\n";
cout << typeid(vb[0].base()).name() << endl;
cout << typeid(vb[1].base()).name() << endl;
cout << "==\n";
*/
}
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