Is appending to lists in Standard ML O(n) time?

Question

I'm trying to insert elements at the end of a list, but I'm wondering if that would be slow?

I know that to append elements in Scheme requires traversing the entire list and thus O(N) time for a list of length N. Is that also true in ML?

Answer 1

This is true in all implementations of ML that I am aware of, though I certainly would believe that it's possible to create an implementation for which that is not the case.