About the non-nullable types debate

Question

I keep hearing people talk about how non-nullable reference types would solve so many bugs and make programming so much easier. Even the creator of null calls it his billion

Answer 1

I admit that I haven't really read a lot about Spec#, but I had understood that the NonNullable was essentially an attribute that you put on a parameter, not necessarily on a variable declaration; Turn your example into something like:

class Class { ... }

void DoSomething(Class c)
{
    if (c == null) return;
    for(int i = 0; i < c.count; ++i) { ... }
}

void main() {
    Class c = nullptr;
    // ... ... ... code ...
    DoSomething(c);
}

With Spec#, you are marking doSomething to say "the parameter c cannot be null". That seems like a good feature to have to me, as it means I don't need the first line in the DoSomething() method (which is an easy to forget line, and completely meaningless to the context of DoSomething()).