using System;

public class Program

{

    public static void Main()

    {

        try

        {

            throw new NotImplementedException();    

        }

        catch (NotImplementedException ex) when (Rethrow(ex, () => Console.WriteLine("First")))

        {

        }

        catch (Exception ex) when (Rethrow(ex, () => Console.WriteLine("Second")))

        {   

        }

    }

        public static bool Rethrow(Exception exception, Action action)

        {

            if (exception == null) throw new ArgumentNullException(nameof(exception));

            if (action == null) throw new ArgumentNullException(nameof(action));

​

            action();

            return false;

        }

}

​

​

​