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

1. VERSION
2. SYNOPSIS
3. DESCRIPTION
4. CONCLUSION
5. AUTHORS
6. COPYRIGHT AND LICENSE

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 <[email protected]>

• Dave Rolsky <[email protected]>

• Jesse Luehrs <[email protected]>

• Shawn M Moore <[email protected]>

• יובל קוג'מן (Yuval Kogman) <[email protected]>

• Karen Etheridge <[email protected]>

• Florian Ragwitz <[email protected]>

• Hans Dieter Pearcey <[email protected]>

• Chris Prather <[email protected]>

• Matt S Trout <[email protected]>

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.