What Compiler-Generated Members Does a C Class Have?

The Compiler-Generated Members of a Class

When creating a class, the compiler implicitly generates specific member functions if certain conditions are met. While these functions are not explicitly declared in the class definition, they play a crucial role in its functionality.

Default Constructor

The default constructor is automatically created if none is explicitly defined in the class. It is a no-argument constructor that initializes members with default values. Its primary purpose is to facilitate object creation without specifying initial values.

Copy Constructor

The copy constructor copies the values of all data members from an existing object of the same class to a newly created object. It enables passing objects by value, making a deep copy of the object.

Copy Assignment Operator

The copy assignment operator assigns the values of all data members from an existing object to an existing object. It allows modifying an existing object's values by copying them from another object of the same class.

Destructor

The destructor is responsible for deallocating memory and performing any necessary cleanup actions when an object is destroyed. It is automatically generated to free resources allocated during object construction.

Member Functions Only Generated When Needed

In C 98/03, the compiler only generates these functions if they are required. In C 11 and later, additional rules apply:

• Move Constructor: Generated if there are no user-defined copy operations, move operations, or destructors and all members are moveable.
• Move Assignment Operator: Similar to the move constructor, but for assignment.

Why Default Constructor Needed

The default constructor serves several purposes:

• Facilitates object creation without arguments.
• Ensures an object can be initialized without specifying values.
• Enables passing objects by value without specifying arguments.
• Provides a default state for objects when explicit initialization is not desired.

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