1. “What is it?” While std::move() is technically a function – I would say it isn’t really a function. It’s sort of a converter between ways the compiler considers an expression’s value. 2. “What does it do?” The first thing to note is that std::move() doesn’t actually move anything. It changes an expression from being … Read more
It depends on the order of data member declarations in the class. So a_ will be the first one, then b_ will be the second one in your example.
When you add the const keyword to a method the this pointer will essentially become a pointer to const object, and you cannot therefore change any member data. (Unless you use mutable, more on that later). The const keyword is part of the functions signature which means that you can implement two similar methods, one … Read more
One way you could do this would be to make the constructors private and only allow construction through a static method that returns a pointer. For example: class Foo { public: ~Foo(); static Foo* createFoo() { return new Foo(); } private: Foo(); Foo(const Foo&); Foo& operator=(const Foo&); };
The four operators mentioned in the original posting, =, (), -> and [], must indeed be implemented as non-static member functions (by respectively C++98 §13.5.3/1, §13.5.4/1, §13.5.5/1 and §13.5.6/1). Bjarne Stroustrup’s rationale was, as I recall from earlier debates on the subject, to retain some sanity in the language, i.e. having at least some things … Read more
The unary prefix operator &, when applied to an object, yields the address of the object: &obj. The type modifier &, when applied to a variable about to be declared, will modify the variable’s type to be a reference type: int&. The same applies to *: When applied as a unary prefix operator to a … Read more
It is because name lookup stops if it finds a name in one of your bases. It won’t look beyond in other bases. The function in B shadows the function in A. You have to re-declare the function of A in the scope of B, so that both functions are visible from within B and … Read more
Reviewing the basic terminology It’s usually good enough – unless you’re programming assembly – to envisage a pointer containing a numeric memory address, with 1 referring to the second byte in the process’s memory, 2 the third, 3 the fourth and so on…. What happened to 0 and the first byte? Well, we’ll get to … Read more
You have to understand the forwarding problem. You can read the entire problem in detail, but I’ll summarize. Basically, given the expression E(a, b, … , c), we want the expression f(a, b, … , c) to be equivalent. In C++03, this is impossible. There are many attempts, but they all fail in some regard. … Read more
All you need to do is declare the class’ new operator private: class X { private: // Prevent heap allocation void * operator new (size_t); void * operator new[] (size_t); void operator delete (void *); void operator delete[] (void*); // … // The rest of the implementation for X // … }; Making ‘operator new’ … Read more