if (matches(sequence.charAt(i))) {
        return i;
      }
    }
    return -1;
  }

  /**
   * Returns the number of matching {@code char}s found in a character sequence.
   *
   * <p>Counts 2 per supplementary character, such as for {@link #whitespace}().{@link #negate}().
   */
  public int countIn(CharSequence sequence) {
    int count = 0;

      if (matches(sequence.charAt(i))) {
        return i;
      }
    }
    return -1;
  }

  /**
   * Returns the number of matching {@code char}s found in a character sequence.
   *
   * <p>Counts 2 per supplementary character, such as for {@link #whitespace}().{@link #negate}().
   */
  public int countIn(CharSequence sequence) {
    int count = 0;