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Special Member Functions

C++ defines several kinds of functions that can be declared only as class members — these are called "special member functions." These functions affect the way objects of a given class are created, destroyed, copied, and converted into objects of other types. Another important property of many of these functions is that they can be called implicitly (by the compiler).

The special member functions described in this section are as follows:

The items in the preceding list can be user-defined for each class.

Special member functions obey the same access rules as other member functions. The access rules are described in Member-Access Control. The following table summarizes how member and friend functions behave.

Summary of Function Behavior

Function Type

Is Function Inherited from Base Class?

Can Function Be Virtual?

Can Function Return a Value?

Is Function a Member or Friend?

Will Compiler Generate Function if User Does Not?

Constructor

No

No

No

Member

Yes

Copy Constructor

No

No

No

Member

Yes

Destructor

No

Yes

No

Member

Yes

Conversion

Yes

Yes

No

Member

No

Assignment (operator=)

No

Yes

Yes

Member

Yes

new

Yes

No

void*

Static member

No

delete

Yes

No

void

Static member

No

Other member functions

Yes

Yes

Yes

Member

No

Friend functions

No

No

Yes

Friend

No

See Also

Concepts

C++ Language Reference