Smart pointers also typically overload operator * as well as operator -> so that they may be used to refer to nonclass types.
除了重载operator->外，智能指针通常还重载operator *, 从而可以用它们指向不是类的类型，如下所示：
CheckedPtr ip = new int;
*ip = 12; // same as ip.operator *() = 12
(*s).draw(); // use on ptr to class, too Smart pointers are used pervasively in C++ programming, from resource handles to STL iterators, to reference counting pointers, to wrappers around pointers to member functions, and on and on.
智能指针在C++编程中广泛使用，从资源句柄到STL迭代器，再到引用计数指针，再到围绕成员函数的指针的包装器，等等。
ref
《C++ COMMON KNOWLEDGE: ESSENTIAL INTERMEDIATE PROGRAMMING》
