c++ - How Many default methods does a class have?

Question

Sorry, this might seem simple, but somebody asked me this, and I don't know for certain.

An empty C++ class comes with what functions?

Constructor, Copy Constructor, Assignment, Destructor?

Is that it? Or are there more?

Answer 1

In C++03 there are 4:

• Default constructor: Declared only if no user-defined constructor is declared. Defined when used

• Copy constructor - declared only if the user hasn't declared one. Defined if used

• Copy-assignment operator same as above

• Destructor same as above

In C++11 there are two more:

• Move constructor
• Move-assignment operator

It is also possible that the compiler won't be able to generate some of them. For example, if the class contains, for example, a reference (or anything else that cannot be copy-assigned), then the compiler won't be able to generate a copy-assignment operator for you. For more information read this