NAME

Sort::Key::Natural - fast natural sorting

SYNOPSIS

    use Sort::Key::Natural qw(natsort);

    my @data = qw(foo1 foo23 foo6 bar12 bar1
		  foo bar2 bar-45 foomatic b-a-r-45);

    my @sorted = natsort @data;

    print "@sorted\n";
    # prints:
    #   b-a-r-45 bar1 bar2 bar12 bar-45 foo foo1 foo6 foo23 foomatic

    use Sort::Key::Natural qw(natkeysort);

    my @objects = (...);
    my @sorted = natkeysort { $_->get_id } @objects;

DESCRIPTION

This module extends the Sort::Key family of modules to support natural sorting.

Under natural sorting, strings are splitted at word and number boundaries, and the resulting substrings are compared as follows:

• numeric substrings are compared numerically

• alphabetic substrings are compared lexically

• numeric substrings come always before alphabetic substrings

Spaces, symbols and non-printable characters are only considered for splitting the string into its parts but not for sorting. For instance foo-bar-42 is broken in three substrings foo, bar and 42 and after that the dashes are ignored.

Note, that the sorting is case sensitive. To do a case insensitive sort you have to convert the keys explicitly:

my @sorted = natkeysort { lc $_ } @data

Also, once this module is loaded, the new type natural (or nat) will be available from Sort::Key::Maker. For instance:

use Sort::Key::Natural;
use Sort::Key::Maker i_rnat_keysort => qw(integer -natural);

creates a multikey sorter i_rnat_keysort accepting two keys, the first to be compared as an integer and the second in natural descending order.

FUNCTIONS

the functions that can be imported from this module are:

natsort @data

returns the elements of @data sorted in natural order.

rnatsort @data

returns the elements of @data sorted in natural descending order.

natkeysort { CALC_KEY($_) } @data

returns the elements on @array naturally sorted by the keys resulting from applying them CALC_KEY.

rnatkeysort { CALC_KEY($_) } @data

is similar to natkeysort but sorts the elements in descending order.

natsort_inplace @data

rnatsort_inplace @data

natkeysort_inplace { CALC_KEY($_) } @data

rnatkeysort_inplace { CALC_KEY($_) } @data

these functions are similar respectively to natsort, rnatsort, natsortkey and rnatsortkey, but they sort the array @data in place.

mkkey_natural $key

transforms key $key in a way that when sorted with Sort::Key keysort results in a natural sort. If the argument $key is not provided it defaults to $_

SEE ALSO

Sort::Key, Sort::Key::Maker.

Other module providing similar functionality is Sort::Naturally.

COPYRIGHT AND LICENSE

Copyright (C) 2006 by Salvador Fandiño, <sfandino@yahoo.com>.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.4 or, at your option, any later version of Perl 5 you may have available.