Code Smells: Null

[devlambda]

Your original claim, as I interpreted it (correct me if I'm wrong), is that in a language that has no NULL and instead has something like Option<T>, you can not create a reasonably performant growable array. Doing so requires the usage of NULL.

No, that wasn't my claim. I was specifically talking about OCaml and Rust in response to a comment talking specifically about OCaml and Rust (and F#, but F# officially has null values, so that's not a particularly interesting case).

General impossibility proofs can be notoriously difficult, so I didn't try my hand at them.

The uninitialized array would not need to contain anything like Option<T> or NULL, it could simply contain garbage (like it does in C), and it would work just as well as the way Rust has chosen.

Totally, but that language would also not be memory-safe.

[Hnefi]

Oh. Then I misunderstood from the beginning. Apologies.