Revised basics recipe 7.

[gitmo/Moose.git] / lib / Moose / Cookbook / Basics / Recipe7.pod

=pod

=head1 NAME

Moose::Cookbook::Basics::Recipe7 - Making Moose fast with immutable

=head1 SYNOPSIS

  package Point;
  use Moose;

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

  __PACKAGE__->meta->make_immutable;

=head1 DESCRIPTION

The Moose metaclass API provides a C<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 invokes 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.

=head1 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 object.

=head1 AUTHOR

Dave Rolsky E<lt>autarch@urth.orgE<gt>

=head1 COPYRIGHT AND LICENSE

Copyright 2006-2009 by Infinity Interactive, Inc.

L<http://www.iinteractive.com>

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

=cut