MooseX::Traits::Attribute::CascadeClear.3pm

Langue: en

Version: 2009-01-17 (fedora - 05/07/09)

Section: 3 (Bibliothèques de fonctions)

Sommaire

NAME

MooseX::Traits::Attribute::CascadeClear - Attribute trait to cascade clearer actions

SYNOPSIS

     # our "master" attribute
     has master => (
         # overrides our clearer method 
         traits     => [ 'CascadeClearMaster' ], 
         is         => 'rw',
         isa        => 'Str',
         lazy       => 1,
         default    => 'nuts',
     );
 
     has client1 => (
         # mark us for clearing on clear_master()
         traits   => [ 'CascadeClear' ], 
         clear_on => 'master', 
         is       => 'ro', 
         isa      => 'Str', 
         lazy     => 1,
         default  => sub { shift->master . "1" }
     );

DESCRIPTION

CascadeClearer is an attribute metaclass trait that allows one to chain attribute clearing actions. For instance, if you have attributes that derive their value from a ``master'' attribute, this would transparently allow you to clear all the children attributes by clearing the master attribute.

USAGE

This trait provides an additional option to attributes, clear_on. It should be used in conjunction with CascadeClearMaster (aka Moose::Meta::Attribute::Custom::Traits::CascadeClearMaster). As attributes are defined, this trait should be specified and the clear_on attribute declared. Declaring a non-existant attribute in clear_on causes neither an error nor a warning.

To use, simply declare CascadeClear as one of your attributes traits, then designate its master attribute through clear_on. The client attribute does not need to have a clearer defined, but if it does, it will be used.

SEE ALSO

MooseX::Traits::Attribute::CascadeClearMaster

This package is part of the Fedora Project's Perl SIG work. For more information, see:

     http://fedoraproject.org
     http://fedoraproject.org/wiki/Perl
     http://camelus.fedorahosted.org

BUGS AND LIMITATIONS

There are no known bugs in this module.

Please report problems or requests to this package's RT tracker at <bug-MooseX-Traits-Attribute-CascadeClear@rt.cpan.org>.

Patches are welcome.

AUTHOR

Chris Weyl <cweyl@alumni.drew.edu> Copyright (c) 2008 Chris Weyl <cweyl@alumni.drew.edu>

This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 2.1 of the License, or (at your option) any later version.

This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA