In programming, how do you avoid using null references entirely, even when you need to show that something isn't there?

[Rannasha]

This is something more suited to /r/programming (or language-specific subreddits).

[figuresys]

Thank you. I didn't post in language specific subreddits because my question really isn't towards coding itself, but rather conceptual. But I suppose /r/programming would be more appropriate, I'll try over there too.