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I refer to this question: What is the copy-and-swap idiom? Effectively, the above answer leads to the following implementation: class MyClass { public: friend void swap(MyClass & lhs, MyClass & rhs) noexcept; MyClass() { /* to implement */ }; virtual ~MyClass() { /* to implement */ }; MyClass(const MyClass & rhs) { /* to implement */ } MyClass(MyClass && rhs) : MyClass() { swap(*this, rhs); } MyClass & operator=(MyClass rhs) { swap(*this, rhs); return *this; } }; void swap( MyClass & lhs, MyClass & rhs ) { using std::swap; /* to implement */ //swap(rhs.x, lhs.x); } However, notice that we could eschew the swap() altogether, doing the following: class MyClass { public: MyClass() { /* to implement */ }; virtual ~MyClass() { /* to implement */ }; MyClass(const MyClass & rhs) { /* to implement */ } MyClass(MyClass && rhs) : MyClass() { *this = std::forward<MyClass>(rhs); } MyClass & operator=(MyClass rhs) { /* put swap code here */ using std::swap; /* to implement */ //swap(rhs.x, lhs.x); // ::: return *this; } }; Note that this means that we will no longer have a valid argument dependent lookup on std::swap with MyClass. In short is there any advantage of having the swap() method. edit: I realized there is a terrible mistake in the second implementation above, and its quite a big thing so I will leave it as-is to instruct anybody who comes across this. if operator = is defined as MyClass2 & operator=(MyClass2 rhs) Then whenever rhs is a r-value, the move constructor will be called. However, this means that when using: MyClass2(MyClass2 &&am

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