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A namespace, in the context of computer programming, refers to the concept of the name of a construct, variable or constant, and within which scopes it is visible.
Example:
class Chicken () : public Bird {
public:
int nWings = 2;
int nLegs = 2;
int bFlight = FALSE;
void Cluck () {}
}
class Hen () : public Chicken {
public:
void LayEggs () {}
}
class Cock () : public Chicken {
public:
void Cockadoodledoo () {}
}
void main () {
Chicken* pClucker; // Chicken pointers can be used with Chickens, Hens and Cocks
pClucker = new Hen; // create a Hen
// The functions Cockadoodledoo (), Cluck (), and LayEggs () are not available at this scope.
// They are within a different namespace.
Cluck (); // This function call will fail, there is no Cluck () in this namespace.
LayEggs (); // This function call will fail, there is no LayEggs () in this namespace.
// These function calls will succeed, because they are being called within a different namespace.
pClucker -> Cluck (); // you can call a Chicken function through a Chicken pointer
pClucker -> LayEggs (); // you can call a Hen function through a Chicken pointer
// If we define Cluck () outside the context of a Chicken...
void Cluck () {}
// ...this function call will now succeed.
Cluck ();
// Note that these two function calls...
pClucker -> Cluck ();
Cluck ();
// Now do two different things, because they are being called from different namespaces;
// the Chicken namespace, and the main () namespace.
}
(This example may have confused the concept of "scope" with the concept of "namespace". Please adjust accordingly.)
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