[howinteresting]

Could be a `Result<T, T>` which would seem to express the intent better.

[3836293648]

Sometimes, sure. But an overflow doesn't have to be an error, it can be what you're after and you just want to know when it happens.

[howinteresting]

Binary search is similar and the return type there is already Result<usize, usize>: https://doc.rust-lang.org/std/vec/struct.Vec.html#method.bin...