Moose::Cookbook::Basics::Immutable - Making Moose fast by making your class immutable

Authors

       •   Stevan Little <stevan@cpan.org>

       •   Dave Rolsky <autarch@urth.org>

       •   Jesse Luehrs <doy@cpan.org>

       •   Shawn M Moore <sartak@cpan.org>

       •   יובל קוג'מן (Yuval Kogman) <nothingmuch@woobling.org>

       •   Karen Etheridge <ether@cpan.org>

       •   Florian Ragwitz <rafl@debian.org>

       •   Hans Dieter Pearcey <hdp@cpan.org>

       •   Chris Prather <chris@prather.org>

       •   Matt S Trout <mstrout@cpan.org>

Conclusion

       We strongly recommend you make your classes immutable. It makes your code much faster, with a small
       compile-time cost. This will be especially noticeable when creating many objects.

Copyright And License

       This software is copyright (c) 2006 by Infinity Interactive, Inc.

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

perl v5.40.0                                       2024-10-20             Moose::Cookbook...sics::Immutable(3pm)

Description

       The Moose metaclass API provides a make_immutable() method. Calling this method does two things to your
       class. First, it makes it faster. In particular, object construction and destruction are effectively
       "inlined" in your class, and no longer invoke the meta API.

       Second, you can no longer make changes via the metaclass API, such as adding attributes. In practice,
       this won't be a problem, as you rarely need to do this after first loading the class.

Name

       Moose::Cookbook::Basics::Immutable - Making Moose fast by making your class immutable

Synopsis

         package Point;
         use Moose;

         has 'x' => ( isa => 'Int', is => 'ro' );
         has 'y' => ( isa => 'Int', is => 'rw' );

         __PACKAGE__->meta->make_immutable;