NAME
    Text::Levenshtein::Damerau::XS - XS Damerau Levenshtein edit distance.

SYNOPSIS
            use Text::Levenshtein::Damerau::XS qw/xs_edistance/;

            print xs_edistance('Neil','Niel');
            # prints 1

DESCRIPTION
    Returns the true Damerau Levenshtein edit distance of strings with
    adjacent transpositions. XS implementation (requires a C compiler).
    Works correctly with utf8.

            use utf8;
            xs_edistance('ⓕⓞⓤⓡ','ⓕⓤⓞⓡ'), 
            # prints 1

    Speed improvements over Text::Levenshtein::Damerau::PP:

            # Text::Levenshtein::Damerau::PP::pp_edistance("four","fuor")
            timethis 1000000: 381 wallclock secs (380.45 usr +  0.01 sys = 
                     380.46 CPU) @ 2628.40/s (n=1000000)

            # Text::Levenshtein::Damerau::XS::xs_edistance("four","fuor")
            timethis 1000000: 19 wallclock secs (19.43 usr +  0.00 sys = 
                     19.43 CPU) @ 51466.80/s (n=1000000)

METHODS
  xs_edistance
    Arguments: source string and target string.

    *   *OPTIONAL 3rd argument* int (max distance; only return results with
        $int distance or less). 0 = unlimited. Default = 0.

    Returns: int that represents the edit distance between the two argument.
    Stops calculations and returns -1 if max distance is set and reached.

    Wrapper function to take the edit distance between a source and target
    string using XS algorithm implementation.

            use Text::Levenshtein::Damerau::XS qw/xs_edistance/;
            print xs_edistance('Neil','Niel');
            # prints 1

           # Max edit distance of 1
            print xs_edistance('Neil','Niely',1); # distance is 2
            # prints -1

TODO
    *   Handle very large strings of text. Can be accomplished by reworking
        the scoring matrix or writing to disk.

    *   Add from_file methods.

    *   Add binary/byte string support.

SEE ALSO
    *   Text::Levenshtein::Damerau

    *   Text::Levenshtein::Damerau::PP

BUGS
    Please report bugs to:

    <https://rt.cpan.org/Public/Dist/Display.html?Name=Text-Levenshtein-Dame
    rau-XS>

AUTHOR
    Nick Logan <ug@skunkds.com>

LICENSE AND COPYRIGHT
    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself.