Sub::HandlesVia::Manual::WithMouse(3) User Contributed Perl Documentation Sub::HandlesVia::Manual::WithMouse(3)

Sub::HandlesVia::Manual::WithMouse - using Sub::HandlesVia with Mouse

package Kitchen {
  use Mouse;
  use Sub::HandlesVia;
  use Types::Standard qw( ArrayRef Str );

  has food => (
    is          => 'ro',
    isa         => ArrayRef[Str],
    handles_via => 'Array',
    default     => sub { [] },
    handles     => {
      'add_food'    => 'push',
      'find_food'   => 'grep',
    },
  );
}

(If you have a mouse in your kitchen, that might not be very hygienic.)

Sub::HandlesVia allows you to delegate methods from your class to the values of your objects' attributes.

Conceptually, it allows you to define "$object->push_number($n)" to be a shortcut for "$object->numbers->push($n)" except that "$object->numbers" is an arrayref, so doesn't have methods you can call on it like "push".

You should be able to use Sub::HandlesVia as a drop-in replacement for MouseX::NativeTraits, just replacing "traits => ['Array']" in an attribute definition with "handles_via => 'Array'".

Mouse roles are only partially supported.

package R1 {
  use Mouse:Role;
}

package R2 {
  use Mouse:Role;
  use Sub::HandlesVia;

  # define some attributes with delegation
}

# This class is broken.
package C1 {
  use Mouse;
  with 'R1', 'R2';
}

# This class should work.
package C2 {
  use Mouse;
  with 'R1';
  with 'R2';
}

For details, see https://github.com/tobyink/p5-sub-handlesvia/issues/9.

Patches to fix the issue are very welcome!

The "handles_via" option indicates which library of methods should be available. Valid values include Array, Blessed, Bool, Code, Counter, Enum, Hash, Number, Scalar, and String.

An arrayref can be provided for "handles_via", though many of the options are conceptually contradictory.

handles_via => [ 'Number', 'Scalar' ]

Although the synopsis shows Types::Standard being used for type constraints, Mouse native types should also work fine.

package Kitchen {
  use Mouse;
  use Sub::HandlesVia;

  has food => (
    is          => 'ro',
    isa         => 'ArrayRef[Str]',
    handles_via => 'Array',
    default     => sub { [] },
    handles     => {
      'add_food'    => 'push',
      'find_food'   => 'grep',
    },
  );
}

Sub::HandlesVia will also recognize MouseX::NativeTraits-style "traits". It will jump in and handle them before MouseX::NativeTraits notices!

package Kitchen {
  use Mouse;
  use Sub::HandlesVia;

  has food => (
    is          => 'ro',
    isa         => 'ArrayRef[Str]',
    traits      => ['Array'],
    default     => sub { [] },
    handles     => {
      'add_food'    => 'push',
      'find_food'   => 'grep',
    },
  );
}

Please report any bugs to https://github.com/tobyink/p5-sub-handlesvia/issues.

Misc advanced documentation: Sub::HandlesVia::Manual::Advanced.

Sub::HandlesVia.

Documentation for delegatable methods: Sub::HandlesVia::HandlerLibrary::Array, Sub::HandlesVia::HandlerLibrary::Blessed, Sub::HandlesVia::HandlerLibrary::Bool, Sub::HandlesVia::HandlerLibrary::Code, Sub::HandlesVia::HandlerLibrary::Counter, Sub::HandlesVia::HandlerLibrary::Enum, Sub::HandlesVia::HandlerLibrary::Hash, Sub::HandlesVia::HandlerLibrary::Number, Sub::HandlesVia::HandlerLibrary::Scalar, and Sub::HandlesVia::HandlerLibrary::String.

Toby Inkster <tobyink@cpan.org>.

This software is copyright (c) 2022 by Toby Inkster.

This is free software; you can redistribute it and/or modify it under the same terms as the Perl 5 programming language system itself.

THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

2024-09-02 perl v5.40.0