C++: A Dialog Programming with the C++ Standard Library

static Member Functions

Give up? Okay. When we declare a member function to be static, we don't have to specify an object when we call the member function. Thus, we can refer to the static member function Today by its name followed by empty parentheses to indicate a function call. Within DatedStockItem member functions, writing “Today();” is sufficient. Of course, if Today were public, and we wanted to call it from a nonmember function, we would have to refer to it by its full name: DatedStockItem::Today(). Either of these calls differs from the normal use of a member function, where we specify the function along with the object to which it applies — for example, in the expression “soup.GetPrice();”.

That explains what the static modifier does, ...