Sort::Key::Maker - multikey sorter creator

  # create a function that sorts strings by length:
  use Sort::Key::Maker sort_by_length => sub { length $_},  qw(integer);

  # create a multikey sort function;
  # first key is integer sorted in descending order,
  # second key is a string in default (ascending) order:
  use Sort::Key::Maker ri_s_keysort => qw(-integer string);

  # some sample data...
  my @foo = qw(foo bar t too tood mama);

  # and now, use the sorter functions previously made:

  # get the values on @foo sorted by length:
  my @sorted = sort_by_length @foo;

  # sort @foo inplace by its length and then by its value:
  ri_s_keysort_inplace { length $_, $_ } @foo;

Sort::Key::Maker is a pragmatic module that provides an easy to use interface to Sort::Key multikey sorting functionality.

It creates multikey sorting functions on the fly for any key type combination and exports them to the caller package.

The key types natively accepted are:

  string, str, locale, loc, integer, int,
  unsigned_integer, uint, number, num

and support for other types can be added via Sort::Key::Register (or also via Sort::Key::register_type()).

use Sort::Key::Maker foo_sort => @keys;

exports two subroutines to the caller package: foo_sort (&@) and foo_sort_inplace (&\@).

Those two subroutines require a sub reference as their first argument and then respectively, the list to be sorted or an array.

For instance:

  use Sort::Key::Maker bar_sort => qw(int int str);

  @bar=qw(doo tomo 45s tio);
  @sorted = bar_sort { unpack "CCs", $_ } @bar;
  # or sorting @bar inplace
  bar_sort_inplace { unpack "CCs", $_ } @bar;

use Sort::Key::Maker foo_sort => \&genmultikey, @keys;

when the first argument after the sorter name is a reference to a subroutine it is used as the multikey extraction function. The generated sorter functions doesn't require neither accept one, i.e.:

  use Sort::Key::Maker sort_by_length => sub { length $_ }, 'int';
  my @sorted = sort_by_length qw(foo goo h mama picasso);

Sort::Key, Sort::Key::Register.

Sort::Maker also available from CPAN provides similar functionality.

Salvador Fandiño, <sfandino@yahoo.com>

Copyright (C) 2005 by Salvador Fandiño

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.