namespace System.ServiceModel
{
    public abstract class ClientBase<TChannel> : IAsyncDisposable, IDisposable, ICommunicationObject
        where TChannel, class
    {
        protected class ChannelBase<T> : IDisposable, IChannel, IOutputChannel, IRequestChannel, IClientChannel, ICommunicationObject, IContextChannel, IExtensibleObject<IContextChannel>
            where T, class
        {
            protected IAsyncResult BeginInvoke(string methodName, object[] args, AsyncCallback callback, object state);
        }
    }
}