perldoc > Moose::Cookbook::Basics::Immutable

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

VERSION
    version 2.2207

SYNOPSIS
      package Point;
      use Moose;

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

      __PACKAGE__->meta->make_immutable;

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.

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.

AUTHORS
    *   Stevan Little <stevan AT cpan.org>

    *   Dave Rolsky <autarch AT urth.org>

    *   Jesse Luehrs <doy AT cpan.org>

    *   Shawn M Moore <sartak AT cpan.org>

    *   יובל קוג'מן (Yuval Kogman) <nothingmuch AT woobling.org>

    *   Karen Etheridge <ether AT cpan.org>

    *   Florian Ragwitz <rafl AT debian.org>

    *   Hans Dieter Pearcey <hdp AT cpan.org>

    *   Chris Prather <chris AT prather.org>

    *   Matt S Trout <mstrout AT cpan.org>

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.