damerau_levenshtein_distance - compute Damerau-Levenshtein distance of two strings

SYNOPSIS
    int damerau_levenshtein_distance(string a, string b)

DESCRIPTION
    Computes the Damarau-Levenshtein distance between strings a and b,
    which is the number of insertions, deletions, replacements or
    transpositions necessary to transform one to the other provided
    that no substring is modified more than once.  For more information,
    see http://en.wikipedia.org/wiki/Damerau-Levenshtein_distance.

EXAMPLE
    > eval -b damerau_levenshtein_distance("kitten", "mittens")
    [Integer] 2
    > eval -b damerau_levenshtein_distance("terrible", "tortuous")
    [Integer] 6
    > eval -b damerau_levenshtein_distance("terrible", "tribble")
    [Integer] 2
    > eval -b damerau_levenshtein_distance("know", "nkow")
    [Integer] 1

SEE ALSO
    levenshtein_distance(sefun), regexp(efun)
