using System.Runtime.CompilerServices;

namespace ConsoleApplication59
{
    class Program
    {
        private static void Main()
        {
            MainAsync();
        }

        private async static void MainAsync()
        {
            await Foo();
        }

        static TA Foo()
        {
            return new TA();
        }
    }

    class TA { }

    static class TAEx
    {
        public static TaskAwaiter GetAwaiter(this TA ta)
        {
            return new TaskAwaiter();
        }
    }
}