Problem Statement

Take a string and reverse it. For example, "asdf" becomes "fdsa".

Preserve Unicode combining characters. For example, "as⃝df̅" becomes "f̅ds⃝a", not "̅fd⃝sa".

Let's start with the solution:

pragma.enable("accumulator")
def reverse(string) {
  return accum "" for i in (0..!(string.size())).descending() { _ + string[i] }
}