# Moose::Cookbook::Basics::Immutable - phpMan

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

## VERSION
    version 2.2200

## 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@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>>

## 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.