/usr/lib/perl5/Moose/Cookbook/Roles/Recipe3.pod is in libmoose-perl 2.0401-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 | package Moose::Cookbook::Roles::Recipe3;
# ABSTRACT: Applying a role to an object instance
=pod
=head1 NAME
Moose::Cookbook::Roles::Recipe3 - Applying a role to an object instance
=head1 VERSION
version 2.0401
=head1 SYNOPSIS
package MyApp::Role::Job::Manager;
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 $employee = first { !$_->has_work } @{ $self->employees };
die 'All my employees have work to do!' unless $employee;
$employee->work($work);
}
package main;
my $lisa = Employee->new( name => 'Lisa' );
MyApp::Role::Job::Manager->meta->apply($lisa);
my $homer = Employee->new( name => 'Homer' );
my $bart = Employee->new( name => 'Bart' );
my $marge = Employee->new( name => 'Marge' );
$lisa->employees( [ $homer, $bart, $marge ] );
$lisa->assign_work('mow the lawn');
=head1 DESCRIPTION
In this recipe, we show how a role can be applied to an object. In
this specific case, we are giving an employee managerial
responsibilities.
Applying a role to an object is simple. The L<Moose::Meta::Role>
object provides an C<apply> method. This method will do the right
thing when given an object instance.
MyApp::Role::Job::Manager->meta->apply($lisa);
We could also use the C<apply_all_roles> function from L<Moose::Util>.
apply_all_roles( $person, MyApp::Role::Job::Manager->meta );
The main advantage of using C<apply_all_roles> is that it can be used
to apply more than one role at a time.
We could also pass parameters to the role we're applying:
MyApp::Role::Job::Manager->meta->apply(
$lisa,
-alias => { assign_work => 'get_off_your_lazy_behind' },
);
We saw examples of how method exclusion and alias working in L<roles
recipe 2|Moose::Cookbook::Roles::Recipe2>.
=begin testing-SETUP
{
# Not in the recipe, but needed for writing tests.
package Employee;
use Moose;
has 'name' => (
is => 'ro',
isa => 'Str',
required => 1,
);
has 'work' => (
is => 'rw',
isa => 'Str',
predicate => 'has_work',
);
}
=end testing-SETUP
=head1 CONCLUSION
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.
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.
=begin testing
{
my $lisa = Employee->new( name => 'Lisa' );
MyApp::Role::Job::Manager->meta->apply($lisa);
my $homer = Employee->new( name => 'Homer' );
my $bart = Employee->new( name => 'Bart' );
my $marge = Employee->new( name => 'Marge' );
$lisa->employees( [ $homer, $bart, $marge ] );
$lisa->assign_work('mow the lawn');
ok( $lisa->does('MyApp::Role::Job::Manager'),
'lisa now does the manager role' );
is( $homer->work, 'mow the lawn',
'homer was assigned a task by lisa' );
}
=end testing
=head1 AUTHOR
Moose is maintained by the Moose Cabal, along with the help of many contributors. See L<Moose/CABAL> and L<Moose/CONTRIBUTORS> for details.
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2011 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.
=cut
__END__
package Moose::Cookbook::Roles::Recipe3;
|