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#include <iostream>
#include <cstring>
using namespace std;
template <class T>
void mswap(T &a, T &b)
{
T tmp(std::move(a));
a = std::move(b);
b = std::move(tmp);
}
struct Data
{
char *text;
void copy(Data const &other)
{
cout << "A " << (void *)other.text << '\n';
text = strdup(other.text);
cout << "B " << (void *)text << '\n';
}
void copy(Data &&other)
{
cout << "D " << (void *)other.text << '\n';
text = other.text;
other.text = 0;
}
};
Data makeData(char const *txt)
{
Data ret;
ret.text = strdup(txt);
cout << "C " << (void *)ret.text << '\n';
return ret;
}
class X
{
public:
X() { cout << "Constructor\n"; }
X(X const &other) { cout << "Copycons\n"; }
X(X &&other) { cout << "Move constructor\n"; }
X &operator=(X const &other) { cout << "std op=\n"; return *this; };
X &operator=(X &&other) { cout << "rref op=\n"; return *this; };
};
X &&fun()
{
X x;
return std::move(x);
}
int main()
{
int &&i = int(3);
++i;
cout << i << '\n';
Data d1 = {strdup("hello")};
Data d2;
d2.copy(d1);
cout << "sep\n";
Data d3;
d3.copy(makeData("hello"));
cout << "sep 2\n";
X &&xr = X();
X x(fun()); // see memory/move.yo:
// No initialization of class objects by rvalues yet
cout << "sep 3\n";
mswap(xr, x);
}
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