As I've worked with more different languages over my career, I've become less and less able to answer those syntax / standard-library questions, simply because there are so many half conflicting memories of other ways to do it.

If the interviewer is any good--big if--they'll mainly be concerned about whether the candidate is making plausible code, regardless of whether it is String.split(s1,s2) or s1.split(s2) or StringUtil.split(s2,s1) ...

I believe you meant `strings.Split(s1, s2)`, but I would have also accepted `s1.split(s2).collect::<Vec<&str>>();`

Kidding aside, I agree completely that syntax isn't the important part. For interviews I think of it more as a sign the person is "warmed" up in a language. If they code in Go or Rust all day currently, then I expect a bit more of the syntax to be known for that language, but it's more a tell on what they actually do all day then what they can do in a week or two of learning.