C++ Namespaces

What is a namespace?

• Namespaces come in handy to avoid name conflicts when multiple programmers are involved.
• Any name in the namespace could be accessed using the scope resolution operator.
• To use the names without any qualifiers (::) keyword "using" is specified. e.g) "using namespace myspace1". All the names are visible in the current scope.

EXAMPLE: Demonstrate the usage of namespaces

#include <iostream>
using namespace std;

void func () {
    cout << "func() in global space" << endl;
}

namespace myspace1 {
    void func () {
        cout << "func() in myspace1" << endl;
    }
}

namespace myspace2 {
    void func () {
        cout << "func() in myspace2" << endl;
    }
}

namespace myspace3 {
    void func1 () {
        cout << "func1() in myspace3" << endl;
    }
}

using namespace myspace3;

void main()
{
    func();
    myspace1::func();
    myspace2::func();
    func1();
}

OUTPUT:

func() in global space
func() in myspace1
func() in myspace2
func1() in myspace3