Title: C# Using alias directives

Just found in section 9.4.1 of the C# language specification: The
`using` keyword can be used to alias a namespace or a type name:

*using-alias-directive: using identifier = namespace-or-type-name ;*

You can read more about that here : [csharp language
specification.doc](http://download.microsoft.com/download/3/8/8/388e7205-bc10-4226-b2a8-75351c669b09/csharp%20language%20specification.doc),
Or just try to use it:

    :::csharp
    // As the specification show it :
    namespace N1.N2
    {
            class A {}
    }
    namespace N3
    {
            using A = N1.N2.A;
            class B: A {}
    }

    // My foobar exemple :
    namespace Foo
    {
            using Bar = Dictionary;
    }

Enjoy!