[remram]

Which language has both a "None" and "null"?

[mynameisash]

Scala, as I recall. It encourages using Options (Some/None), but since it runs on the JVM and will often interop with Java libraries, you can also have nulls.

Not exactly a language design, but an unfortunate reality.

[remram]

Oh no! Does it not have a type for NonNull references, like Rust does?

[kaba0]

Since Scala 3, it can have total static analysis where nulls become a separate type that has to be explicitly declared in type signatures.

So, yes.

[efficax]

javascript, at least, has "undefined" and "null", an infuriating duality of falsiness. PHP also has a notion of not being set as well as being set but null.

[remram]

JavaScript is what we are talking about in this thread, making the point that JavaScript is similar to JavaScript does not help ;-)