What about a simpler way: 
package Automatic::Check;

use Moose::Role;

requires qw(wrapped check_ref assert_check_ref);

sub call {
    my $self = shift;
    my $method = shift;
    
    my $check_ref = $self->check_ref;
    $self->wrapped->$method(@_, $check_ref);
    $self->assert_check_ref($check_ref);
    warn 'ok';
}

package FakeOLE;

sub new { bless {} }

sub LoadObjects {
    my $self = shift;
    my $cfg  = shift;
    $_[0] = $cfg ? 0 : -1;
}

package SA::Application;

use Moose;

has wrapped => ( is => 'ro', builder => '_build_ole');

with qw/Automatic::Check/;

sub _build_ole {
    return FakeOLE->new;
}

sub check_ref { 1 }

sub assert_check_ref {
    my ($self, $check_ref) = @_;

    die "error" unless ( $check_ref == 0 );
}

package main;

my $cfg = 'somefile.cfg';
my $sa = SA::Application->new();
$sa->call('LoadObjects', $cfg); # ok
$sa->call('LoadObjects', 0);    # dies

[download]
Here the role could be applied to any of your wrapper classes as long as they provide methods to get the wrapped object, the validation logic and the $rcref.

In reply to Re: getting automatic error checking with Win32::OLE and Moose by Arunbear
in thread getting automatic error checking with Win32::OLE and Moose by glasswalk3r

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