C++ Primer, Fifth Edition

14.4. Assignment Operators

In addition to the copy- and move-assignment operators that assign one object of the class type to another object of the same type (§ 13.1.2, p. 500, and § 13.6.2, p. 536), a class can define additional assignment operators that allow other types as the right-hand operand.

As one example, in addition to the copy- and move-assignment operators, the library vector class defines a third assignment operator that takes a braced list of elements (§ 9.2.5, p. 337). We can use this operator as follows:

vector<string> v;v = {"a", "an", "the"};

We can add this operator to our StrVec class (§ 13.5, p. 526) as well:

class StrVec {public:    StrVec &operator=(std::initializer_list<std::string>);    // other members as in § 13.5 ...