Special Member Functions

Special member functions in C++ are functions which the compiler will automatically generate if they are used, but not declared explicitly by the programmer. The special member functions are:

  • Default constructor (if no other constructor is explicitly declared)
  • Copy constructor if no move constructor or move assignment operator is explicitly declared.
If a destructor is declared generation of a copy constructor is deprecated.
  • Move constructor if no copy constructor, move assignment operator or destructor is explicitly declared.
  • Copy assignment operator if no move constructor or move assignment operator is explicitly declared.
If a destructor is declared generation of a copy assignment operator is deprecated.
  • Move assignment operator if no copy constructor, copy assignment operator or destructor is explicitly declared.
  • Destructor

In these cases the compiler generated versions of these functions perform a memberwise operation. For example the compiler generated destructor will destroy each sub-object (base class or member) of the object.

The compiler generated functions will be public, non-virtual and the copy constructor and assignment operators will receive const& parameters (and not be of the alternative legal forms).

Read more about Special Member Functions:  Example, Signatures, C++98

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