10 let operator= return a reference to *this

Clause -10 Make operator= Return to one reference to *this

• Make the assignment （saaignment） The operator returns a reference to *this.

Constants have the following assignment chain form ：

int x, y, z;
x = y = z = 15;

// x = ( y = (z = 15) )
// 15 First assigned to z, Then the result （ Updated z） Then assigned to y, Similarly, assign to x.

In order to achieve “ Chain assignment ”, The assignment operator must return a reference Point to the left argument of the operator . stay copy assignment Operator returns *this that will do ：

class widget {
	public:
		……
	widget& operator= ( const widget& rhs ) {
		……
		return *this;
	}
	……
};

The same applies to +=、-+、*=