See https://en.wikipedia.org/wiki/Damerau%E2%80%93Levenshtein_distance , at least for the `edit_distance` part (not sure if the automaton will accept).
See https://en.wikipedia.org/wiki/Damerau%E2%80%93Levenshtein_distance , at least for the
edit_distancepart (not sure if the automaton will accept).