sub work {
  my $something_wrong = 1;
  if( $something_wrong ){
    #return Error->new(0, "because ...");
    return bless [0, "because ..."] => 'Error'
  }
  # edit: changed to a hashref to show returning different types
  # it need not be a ref at all, e.g. can send a hash too
  #return [1,2,3]
  return {1=>2, 3=>4}
}

my $ret = work();
if( ref($ret) eq 'Error' ){ die "error: @$ret" }
print "got some results:".Dumper($ret);