The Simons     Component Library

           

---

Null Class Reference

#include <Object.h>

Inheritance diagram for Null:

List of all members.

---

Detailed Description

Null: the vacuous type of null references.

The Null class has a single distinguished instance, null, which is used to initialise all empty ObjectID references. Null is provided as a disjoint type in the class hierarchy, such that no other object may be promoted to Null. All ObjectID variables have one Null* constructor which is distinct from all other constructors, to allow initialisation with null. Assignment to Null requires implicit conversion from Null* to the required type using this constructor. Equality testing against Null* also converts from Null* to the required type using this constructor.

Public Member Functions
	Null ()
	Create the unique instance of Null.
virtual	~Null ()
	Release the unique instance of Null.

---

Constructor & Destructor Documentation

Null::Null (   )  [inline]

Create the unique instance of Null.

Null::~Null (   )  [inline, virtual]

Release the unique instance of Null.

---

The documentation for this class was generated from the following file:

• Object.h

---