print STDERR "FUNCTION IS ($func)\n";

            print STDERR "(\&is_int) TRUE!\n"
              if &is_int(42, 1);

            print STDERR "(is_int) TRUE!\n"
              if is_int(42, 1);

            print STDERR "(Module::Configurable::is_int) TRUE!\n"
              if Module::Configurable::is_int(42, 1);

            no strict 'refs';
            print STDERR "(\&\$func) TRUE!\n"  # line 137 from output below
              if &$func(42, 1);  # line that's dieing