Sort::Key::Register(3)                     User Contributed Perl Documentation


NAME
       Sort::Key::Register - tell Sort::Key how to sort new data types.

SYNOPSIS
         use Sort::Key::Register Person =>
             sub { $_->surname, $_->name },
             qw(string string);

         use Sort::Key::Register 'Color::Component' => 'integer';

         use Sort::Key::Register Color =>
             sub { $_->R, $_->G, $_->B },
             ('Color::Component') x 3;

DESCRIPTION
       Sort::Key::Register allows one to register new data types with
       Sort::Key so that they can be sorted as natively supported ones.

       It works as a pragma module and doesn't export any function, all its
       functionality is provided via "use":

         use Sort::Key::Register ...

       To avoid collisions between modules registering types with the same
       name, you should qualify them with the package name.

         use Sort::Key::Register 'MyPkg::foo' => sub { $_ }, '-int';

         # or using __PACKAGE__:
         use Sort::Key::Register __PACKAGE__, sub { $_ }, '-int';

   USAGE
       use Sort::Key::Register $name => \&multikeygen, @keytypes;
           registers type $name.

           &multikeygen is the multi-key extraction function for the type and
           @keytypes are the types of the extracted keys.

       use Sort::Key::Register $name => $keytype;
           this 'use' is useful for simple types that are sorted as another
           type already registered, maybe changing the direction of the sort
           (ascending or descending).

SEE ALSO
       Sort::Key, Sort::Key::Maker.

AUTHOR
       Salvador Fandino, <sfandino@yahoo.com>

COPYRIGHT AND LICENSE
       Copyright (C) 2005, 2014 by Salvador Fandino

       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.

perl v5.38.0                      2023-07-25            Sort::Key::Register(3)