NAME<\/a> Moose::Cookbook::Roles::ApplicationToInstance \u2212 Applying a role to an object instance<\/p>\n version 2.2014<\/p>\n package MyApp::Role::Job::Manager; In this recipe, we show how a role can be applied to an object. In this specific case, we are giving an employee managerial responsibilities.<\/p>\n Applying a role to an object is simple. The Moose::Meta::Role object provides an “apply” method. This method will do the right thing when given an object instance.<\/p>\n MyApp::Role::Job::Manager\u2212>meta\u2212>apply($lisa);<\/p>\n We could also use the “apply_all_roles” function from Moose::Util.<\/p>\n apply_all_roles( $person, MyApp::Role::Job::Manager\u2212>meta );<\/p>\n The main advantage of using “apply_all_roles” is that it can be used to apply more than one role at a time.<\/p>\n We could also pass parameters to the role we\u2019re applying:<\/p>\n MyApp::Role::Job::Manager\u2212>meta\u2212>apply( We saw examples of how method exclusion and alias working in Moose::Cookbook::Roles::Restartable_AdvancedComposition.<\/p>\n Applying a role to an object instance is a useful tool for adding behavior to existing objects. In our example, it is effective used to model a promotion.<\/p>\n It can also be useful as a sort of controlled monkey-patching for existing code, particularly non-Moose code. For example, you could create a debugging role and apply it to an object at runtime.<\/p>\n
VERSION<\/a>
SYNOPSIS<\/a>
DESCRIPTION<\/a>
CONCLUSION<\/a>
AUTHORS<\/a>
COPYRIGHT AND LICENSE<\/a> <\/p>\n
\nNAME <\/a> <\/h2>\n
VERSION <\/a> <\/h2>\n
SYNOPSIS <\/a> <\/h2>\n
use List::Util qw( first );
use Moose::Role;
has ‘employees’ => (
is => ‘rw’,
isa => ‘ArrayRef[Employee]’,
);
sub assign_work {
my $self = shift;
my $work = shift;
my $employee = first { !$_\u2212>has_work } @{ $self\u2212>employees };
die ‘All my employees have work to do!’ unless $employee;
$employee\u2212>work($work);
}
package main;
my $lisa = Employee\u2212>new( name => ‘Lisa’ );
MyApp::Role::Job::Manager\u2212>meta\u2212>apply($lisa);
my $homer = Employee\u2212>new( name => ‘Homer’ );
my $bart = Employee\u2212>new( name => ‘Bart’ );
my $marge = Employee\u2212>new( name => ‘Marge’ );
$lisa\u2212>employees( [ $homer, $bart, $marge ] );
$lisa\u2212>assign_work(‘mow the lawn’);<\/p>\nDESCRIPTION <\/a> <\/h2>\n
$lisa,
\u2212alias => { assign_work => ‘get_off_your_lazy_behind’ },
);<\/p>\nCONCLUSION <\/a> <\/h2>\n
AUTHORS <\/a> <\/h2>\n
| <\/td>\n | \n \u2022<\/p>\n<\/td>\n | <\/td>\n | \n Stevan Little \u2022<\/p>\n<\/td>\n Dave Rolsky \u2022<\/p>\n<\/td>\n Jesse Luehrs \u2022<\/p>\n<\/td>\n Shawn M Moore \u2022<\/p>\n<\/td>\n \u00d7\u00d7\u00d7\u00d7 \u00d7\u00a7\u00d7\u00d7\u2019\u00d7\u00d7 (Yuval Kogman) \u2022<\/p>\n<\/td>\n Karen Etheridge \u2022<\/p>\n<\/td>\n Florian Ragwitz \u2022<\/p>\n<\/td>\n Hans Dieter Pearcey \u2022<\/p>\n<\/td>\n |