Rust

Note: the ᐸᐳ characters used below are Canadian Aboriginal syllabics because Lemmy devs haven't fixed broken input sanitization yet.

A vec and a string are basically the same thing (a series of bytes)

Everything is a series of bytes! I thought you were going to mention that both are fat pointers. But that "series of bytes" description is quite weird.

This makes handling it much easier because you can still iterate over it

This is not a valid consideration/objection, as Options are iterable and you can flatten them:

fn main() {
  let v = vec![1,2,3];
  for n in Some(&v).into_iter().flatten() {
    eprintln!("{n}");
  }
  for n in None::ᐸ&Vecᐸi32ᐳᐳ.into_iter().flatten() {
    eprintln!("{n}");
  }
}

This might involve the compiler making an allocation of an empty array but most of them (gcc, ghc) will now what you are doing and optimize the null check on the empty array to a bool check

This paragraph appears to be out of place in the context of a Rust discussion.

Vec::new is const and thus can’t allocate anyways.

In the context of vectors I prefer my APIs to return an empty set rather than an None-option. This makes handling it much easier because you can still iterate over it, it just has nothing.

I can see that argument. But you can also iterate over an Option-wrapped response with something like for x in xs.into_iter().flatten() { ... }, and the Option gives you an extra bit of information that can be helpful in certain cases.