Re: Adding a method to an existing object

in reply to Adding a method to an existing object

I use a similar technique for a very simple plugin system. The main object is a Moose object, and all of the plugins are Moose roles. With in the main class (call it MyApp), I have a method:

sub create_with_roles
{
    my ($class, $roles, %args) = @_;

    for my $role (@$roles)
    {
        next if $role =~ /::/;
        $role = 'MyApp::Role::' . $role;
    }

    Moose::Util::ensure_all_roles( $class, @$roles );
    return $class->new( %args );
}
[download]

... and within the drive program, I can write:

my $app = MyApp->create_with_roles(
    [qw( List Of Role Names )],
    %constructor_arguments
);
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... and get back an object which is an instance of MyApp which performs all of the named roles. It's been working very well.

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Re^2: Adding a method to an existing object by phaylon (Curate) on Feb 17, 2012 at 19:06 UTC
Note that this will permanently change the MyApp class, which might not be what is desired. I tend to use MooseX::Traits in most of the general cases. Ordinary morality is for ordinary people. -- Aleister Crowley	[reply]
Re^3: Adding a method to an existing object by chromatic (Archbishop) on Feb 17, 2012 at 19:20 UTC
I should have mentioned that. It's no problem in my case, because I know none of the plugins will override each other (and no code wants to use an unmodified `MyApp` object), but Moose traits are more general and applicable.	[reply] [d/l]

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