`Interpolation.pm`

        use Eval;

        print "6 * 7 + 53 is $eval{6 * 7 + 53}.\n";

                (prints `6 * 7 + 53 is 95.')

        use Eval ':';

        print "Brain D Foy in lowercase is $:{lc 'Brain D Foy'}.\n";

                (prints `Brain D Foy in lowercase is brain d foy.')

        sub FETCH {
          $_[1];
        }