NAME

       Class::Meta::Types::Boolean - Boolean data types

SYNOPSIS

         package MyApp::Thingy;
         use strict;
         use Class::Meta;
         use Class::Meta::Types::Boolean;
         # OR...
         # use Class::Meta::Types::Boolean 'affordance';
         # OR...
         # use Class::Meta::Types::Boolean 'semi-affordance';

         BEGIN {
             # Create a Class::Meta object for this class.
             my $cm = Class::Meta->new( key => 'thingy' );

             # Add a boolean attribute.
             $cm->add_attribute( name => 'alive',
                                 type => 'boolean' );
             $cm->build;
         }

DESCRIPTION

       This module provides a boolean data type for use with Class::Meta attributes.  Simply load it, then pass
       "boolean" (or the alias "bool") to the "add_attribute()" method of a Class::Meta object to create an
       attribute of the boolean data type. See Class::Meta::Type for more information on using and creating data
       types.

   Accessors
       Although the boolean data type has both "default" and "affordance" accessor options available, unlike the
       other data types that ship with Class::Meta, they have different implementations. The reason for this is
       to ensure that the value of a boolean attribute is always 0 or 1.

       For the "default" accessor style, there is no difference in the interface from the default accessors for
       other data types. The default accessor merely checks the truth of the new value, and assigns 1 if it's a
       true value, and 0 if it's a false value. The result is an efficient accessor that maintains the
       consistency of the data.

       For the "affordance" accessor style, however, the boolean data type varies in the accessors it creates.
       For example, for a boolean attributed named "alive", instead of creating the "get_alive" and "set_alive"
       accessors common to other affordance-style accessors, it instead creates three:

       "is_alive"
       "set_alive_on"
       "set_alive_off"

       The result is highly efficient accessors that ensure the integrity of the data without the overhead of
       validation checks.

SUPPORT

       This module is stored in an open GitHub repository <http://github.com/theory/class-meta/>. Feel free to
       fork and contribute!

       Please file bug reports via GitHub Issues <http://github.com/theory/class-meta/issues/> or by sending
       mail to bug-Class-Meta@rt.cpan.org <mailto:bug-Class-Meta@rt.cpan.org>.

AUTHOR

       David E. Wheeler <david@justatheory.com>

SEE ALSO

       Other classes of interest within the Class::Meta distribution include:

       Class::Meta
           This class contains most of the documentation you need to get started with Class::Meta.

       Class::Meta::Type
           This class manages the creation of data types.

       Class::Meta::Attribute
           This class manages Class::Meta class attributes, all of which are based on data types.

       Other data type modules:

       Class::Meta::Types::Perl
       Class::Meta::Types::String
       Class::Meta::Types::Numeric

COPYRIGHT AND LICENSE

       Copyright (c) 2002-2011, David E. Wheeler. Some Rights Reserved.

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