SYNOPSIS
use Sort::Key::Natural qw(natsort);
my @data = qw(foo1 foo23 foo6 bar12 bar1
foo bar2 bar45 foomatic bar45);
my @sorted = natsort @data;
print "@sorted\n";
# prints:
# bar45 bar1 bar2 bar12 bar45 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 split 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 nonprintable characters are only considered for splitting the string into its parts but not for sorting. For instance "foobar42" 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 $_ } @data
Also, once this module is loaded, the new type "natural" (or "nat") will be available from Sort::Key::Maker. For instance:
use Sort::Key::Natural; use Sort::Key::Maker i_rnat_keysort => qw(integer natural);
creates a multikey sorter "i_rnat_keysort" accepting two keys, the first to be compared as an integer and the second in natural descending order.
There is also an alternative set of natural sorting functions that recognize floating point numbers. They use the key type "natwf" (abbreviation of "natural_with_floats").
FUNCTIONS
the functions that can be imported from this module are: natsort @data
 returns the elements of @data sorted in natural order.
 rnatsort @data
 returns the elements of @data sorted in natural descending order.
 natkeysort { CALC_KEY($_) } @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.
 $key = mkkey_natural $string

given $string, returns a key that can be compared lexicographically
to another key obtained in the same manner, results in the same order
as comparing the former strings as in the natural order.
If the argument $key is not provided it defaults to $_.
 natwfsort @data
 rnatwfsort @data
 natwfkeysort { CALC_KEY($_) } @data
 rnatwfkeysort { CALC_KEY($_) } @data
 natwfsort_inplace @data
 rnatwfsort_inplace @data
 natwfkeysort_inplace { CALC_KEY($_) } @data
 rnatwfkeysort_inplace { CALC_KEY($_) } @data
 mkkey_natural_with_floats $key

this ugly named set of functions perform in the same way as its
s/natwf/nat/ counterpart with the difference that they honor floating
point numbers embedded inside the strings.
In this context a floating point number is a string matching the regular expression "/[+\]?\d+(\.\d*)?/". Note that numbers with an exponent part (i.e. "1.12E12") are not recognized as such.
Note also that numbers without an integer part (i.e. .2 or ".12") are not supported either.
COPYRIGHT AND LICENSE
Copyright (C) 2006, 2012, 2014 by Salvador FandiĆ±o, <[email protected]>.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.