code: public static boolean isBaseForm(int ch)
      {
          int cat = getType(ch);
          // if props == 0, it will just fall through and return false
          return cat == UCharacterCategory.DECIMAL_DIGIT_NUMBER ||
                  cat == UCharacterCategory.OTHER_NUMBER ||
                  cat == UCharacterCategory.LETTER_NUMBER ||
                  cat == UCharacterCategory.UPPERCASE_LETTER ||
                  cat == UCharacterCategory.LOWERCASE_LETTER ||
                  cat == UCharacterCategory.TITLECASE_LETTER ||
                  cat == UCharacterCategory.MODIFIER_LETTER ||
                  cat == UCharacterCategory.OTHER_LETTER ||
                  cat == UCharacterCategory.NON_SPACING_MARK ||
                  cat == UCharacterCategory.ENCLOSING_MARK ||
                  cat == UCharacterCategory.COMBINING_SPACING_MARK;
      }
docs: <strong>[icu]</strong> Determines whether the specified code point is of base form.
  A code point of base form does not graphically combine with preceding
  characters, and is neither a control nor a format character.
  @param ch code point to be determined if it is of base form
  @return true if the code point is of base form