using System;

using System.Collections.Generic;

using System.Linq;

​

public static class GeneralExtensions

{

    public static T Cast<T>(this object o)

    {

        return (T)o;

    }

}

​

public static class EnumExtenstions

{

    public static IEnumerable<string> GetSomethingInLinq(this IEnumerable<object> collection)

    {

        return (from object value in collection select value.ToString() ).ToList();

    }

}

public class Program

{

    public static void Main()

    {

        Console.WriteLine("Hello World");

    }

}