Do you think it is sane to store and use Catalyst application class in controller (in Moose attribute)? I can use the property to link to other application components "statically" without using $c and also store them in attributes.

I mean something like this:

package MyApp::Controller::Region;
use Moose;

BEGIN { extends qw(Catalyst::Controller); }

has app_class => ( is => 'ro' );

has regions => (
    is         => 'ro',
    required   => 1,
    lazy       => 1,
    isa        => 'ArrayRef',
    auto_deref => 1,
    default    => sub {
        # using model and storing bit of data in attributes
        return [ shift()->region_rs->all ];
    }
);

# remembering app_class
around BUILDARGS => sub {
    my $next = shift;
    return { %{ $next->(@_) }, app_class => $_[1], };
};

sub region_rs {
    # accessing the model
    return shift()->app_class->model('DB::Region');
}
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Do you see any potential danger in this?