Can a class share a namespace's name?

Question

Is the following C++ code valid?

namespace Foo
{
    class Bar
    {
        // Class code here.
    };
}

namespace Foo
{
    namespace Bar
    {
        void SomeFunction();
        {
            // Function code here.
        }
    }
 }

In other words, can there be a namespace with the same name as a class?

Solution 1

You cannot have the arrangement you have in your question because there is no way to disambiguate Bar.

My compiler says:

error C2757: 'Bar' : a symbol with this name already exists and therefore this name cannot be used as a namespace name

Solution 2

"can there be a namespace with the same name as a class?"

No, If they are in the same namespace, as in your case.

Otherwise, yes. Anything can have the same name as anything else if they are in different namespaces. See this stackoverflow thread as reference.

Solution 3

No, but you can have SomeFunction be a static member of the Bar class.

namespace Foo
{
    class Bar
    {
        // Class code here.
        static void SomeFunction()
        {
            // Function code here.
        }
    };
}

The result is not 100% equivalent to what you want (because of ADL) but the qualified names are what you expect.

Comments

[Mike Seymour]

No, that question is about using the same name in different namespaces.

[quamrana]

@Mike: I think that Ozair has answered the second question of the OP.

[Ozair Kafray]

@quamrana: Yes, I did answer the second part of the question.

[Mike Seymour]

OK. To clarify this answer: anything can have the same name as anything else if they are in different namespaces; a class cannot have the same name as a namespace if they are both in the same namespace.