NullableCSharp8.cs

  #nullable enable
  namespace CSharpEightTests
  {
      class Developer
      {
          public string FirstName { get; set; }
          public string? LastName { get; set; }

          public Developer(string firstName)
          {
              FirstName = firstName;
              LastName = null;
          }
      }

      class Program
      {
          static void Main(string[] args)
          {
              var jsDev = new Developer("Dawid");
              var devInitials = GetInitials(jsDev);
          }

          static string GetInitials(Developer jsDev)
          {
              if(jsDev.LastName != null)
                  return $"{jsDev.FirstName[0]}{jsDev.LastName[0]}";
              else
                  return $"{jsDev.FirstName[0]}";

          }
      }
  }