What is move constructor in C++11?

A move constructor enables the resources owned by an rvalue object to be moved into an lvalue without copying. For more information about move semantics, see Rvalue Reference Declarator: &&. This topic builds upon the following C++ class, MemoryBlock , which manages a memory buffer.

What does the default move constructor do?

Implicitly-defined move constructor For non-union class types (class and struct), the move constructor performs full member-wise move of the object’s bases and non-static members, in their initialization order, using direct initialization with an xvalue argument.

What is the use of std :: move?

std::move is used to indicate that an object t may be “moved from”, i.e. allowing the efficient transfer of resources from t to another object. In particular, std::move produces an xvalue expression that identifies its argument t . It is exactly equivalent to a static_cast to an rvalue reference type.

How does move work in C++?

In C++11, std::move is a standard library function that casts (using static_cast) its argument into an r-value reference, so that move semantics can be invoked. Thus, we can use std::move to cast an l-value into a type that will prefer being moved over being copied.

What does the move assignment operator do?

In the C++ programming language, the move assignment operator = is used for transferring a temporary object to an existing object. The move assignment operator, like most C++ operators, can be overloaded. Like the copy assignment operator it is a special member function.

Are move constructor automatically generated?

The move constructor is auto-generated if there is no user-declared copy constructor, copy assignment operator or destructor, and if the generated move constructor is valid (§12.8/10).

Is there a default move constructor?

A copy/move constructor that is defaulted and not defined as deleted is implicitly defined if it is odrused (3.2) or when it is explicitly defaulted after its first declaration. [ Note: The copy/move constructor is implicitly defined even if the implementation elided its odr-use (3.2, 12.2).

What is a move constructor?

A move constructor allows the resources owned by an rvalue object to be moved into an lvalue without creating its copy. An rvalue is an expression that does not have any memory address, and an lvalue is an expression with a memory address.

Is move constructor automatically generated?