damerau-levenstein

https://github.com/DarkWater666/damerau-levenshtein

This gem implements pure Levenshtein algorithm, Damerau modification (where 2 character transposition counts as 1 edit distance). It also includes Boehmer & Rees 2008 modification, to handle transposition in blocks with more than 2 characters (Boehmer & Rees 2008).