Reading notes _EFFECTIVE_C++_ clause 25: Consider writing out a swap function that does not throw an exception

The operator= of the previously called object is to do so

    void Swap (a& x)    {        Std::swap (A, x.a);    }    Aoperator= (const a& a)    {        = A;        Swap (temp);         return *this;    }

The code above looks a bit cumbersome, but it's a good idea.

We can make our swap special in Std.

classa{Private:    intA; Public:    voidSwap (a& x)//prevent written friend, we give him an interface{Std::swap (A, x.a); } A (intx): A (x) {} A&operator=(Consta&a) {a temp=A; usingStd::swap; Swap (* This, temp); return* This; }    voiddisplay () {cout<< a <<Endl; }};namespacestd{//template<> The book, but I found that I could not    voidSwap<a> (a &s1, A &s2)//This <A> is a special, and heavy-duty parted {S1.swap (S2); }}intMain () {A A (1); A B (2);    B.display (); b=A; B.display ();}

When class is a template, then again.

Reading notes _EFFECTIVE_C++_ clause 25: Consider writing out a swap function that does not throw an exception