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// Copyright (c) 2015 Egor Tensin <Egor.Tensin@gmail.com>
// This file is part of the "C++ notes" project.
// For details, see https://github.com/egor-tensin/cpp-notes.
// Distributed under the MIT License.
#include <iostream>
#include <utility>
namespace
{
class C
{
public:
explicit C()
{
std::cout << "\tC::C()\n";
}
C(C&&) noexcept
{
std::cout << "\tC::C(C&&)\n";
}
C(const C&)
{
std::cout << "\tC::C(const C&)\n";
}
C& operator=(C&&) noexcept
{
std::cout << "\tC::operator=(C&&)\n";
return *this;
}
C& operator=(const C&)
{
std::cout << "\tC::operator=(const C&)\n";
return *this;
}
~C()
{
std::cout << "\tC::~C()\n";
}
};
C make_rvo()
{
return C{};
}
C make_prevent_rvo()
{
return std::move(C{});
}
C make_nrvo()
{
C c;
return c;
}
C make_prevent_nrvo()
{
C c;
return std::move(c);
}
}
int main()
{
{
std::cout << "C c\n";
C c;
}
{
std::cout << "C c(make_rvo())\n";
C c(make_rvo());
}
{
std::cout << "C c{make_rvo()}\n";
C c{make_rvo()};
}
{
std::cout << "C c = make_rvo()\n";
C c = make_rvo();
}
{
std::cout << "C c(make_nrvo())\n";
C c(make_nrvo());
}
{
std::cout << "C c{make_nrvo())\n";
C c{make_nrvo()};
}
{
std::cout << "C c = make_nrvo()\n";
C c{make_nrvo()};
}
{
std::cout << "C c(make_prevent_rvo())\n";
C c(make_prevent_rvo());
}
{
std::cout << "C c{make_prevent_rvo()}\n";
C c{make_prevent_rvo()};
}
{
std::cout << "C c = make_prevent_rvo()\n";
C c = make_prevent_rvo();
}
{
std::cout << "C c(make_prevent_nrvo())\n";
C c(make_prevent_nrvo());
}
{
std::cout << "C c{make_prevent_nrvo()}\n";
C c{make_prevent_nrvo()};
}
{
std::cout << "C c = make_prevent_nrvo()\n";
C c = make_prevent_nrvo();
}
return 0;
}
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