source: gs2-extensions/parallel-building/trunk/src/perllib/cpan/Sort/Key/Maker.pm@ 27037

package Sort::Key::Maker;

our $VERSION = '0.02';

use warnings;
use strict;

use Sort::Key qw(multikeysorter multikeysorter_inplace);

use Carp;
our @CARP_NOT = qw(Sort::Key);

sub import {
    my $class = shift;
    my $name = shift;
    my $caller = caller;

    no strict 'refs';
    *{"${caller}::${name}"} = multikeysorter @_;
    *{"${caller}::${name}_inplace"} = multikeysorter_inplace @_;
}

1;

__END__

=head1 NAME

Sort::Key::Maker - multikey sorter creator

=head1 SYNOPSYS

  # 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;


=head1 DESCRIPTION

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 L<Sort::Key::Register> (or
also via L<Sort::Key::register_type()>).

=head2 USAGE

=over 4

=item use Sort::Key::Maker foo_sort =E<gt> @keys;

exports two subroutines to the caller package: C<foo_sort (&@)> and
C<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;

=item use Sort::Key::Maker foo_sort =E<gt> \&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);

=back

=head1 SEE ALSO

L<Sort::Key>, L<Sort::Key::Register>.

L<Sort::Maker> also available from CPAN provides similar
functionality.

=head1 AUTHOR

Salvador FandiE<ntilde>o, E<lt>[email protected]<gt>

=head1 COPYRIGHT AND LICENSE

Copyright (C) 2005 by Salvador FandiE<ntilde>o

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.

=cut