Exer07_40_Book.h

// Note: this is a redefinition from chapter 14. It covers contents beyond chapter 7.
#ifndef EXER07_40_BOOK_H
#define EXER07_40_BOOK_H
#include <string>
#include <utility>
using std::string;
class Book {
public:
    Book() = default;
    Book(string na, string au = "", string no = "") :
        book_name(na), book_author(au), book_no(no) {}
    // copy control constructor
    Book(const Book&) = default; // copy constructor
    Book(Book &&b) noexcept :// move constructor
        book_name(std::move(b.book_name)),
        book_author(std::move(b.book_author)),
        book_no(std::move(book_no)) {}
    Book& operator=(const Book&) = default; // copy-assignment operator
    Book& operator=(Book&&) noexcept; // move assignment operator
    ~Book() = default;
private:
    string book_name;
    string book_author;
    string book_no;
};
Book& Book::operator=(Book &&rhs) noexcept
{
    if(this != &rhs)
    {
        book_name = std::move(rhs.book_name);
        book_author = std::move(rhs.book_author);
        book_no = std::move(rhs.book_no);
    }
    return *this;
}
#endif