Is there a way to join the elements in an js array, but let the last separator be different?

Question

What I want is something like Array.join(separator), but which takes a second argument Array.join(separator, beforeLastElement), so when I say [f

Answer 1

No, this is specific enough that you will have to write a custom function. The good news is, as you said, once you use Array.join to take care of all the separators, the last one will be easy enough to update.