code: public static String convertPatternToPerlRegex(@Nonnull final Pattern pattern) {
  		Check.notNull(pattern, "pattern");
  		final String modifiers = Flag.convertToModifiers(Flag.parse(pattern.flags()));
  		return String.format(PATTERN_TO_REGEX_TEMPLATE, pattern.pattern(), modifiers);
  	}
docs: Converts a given {@code Pattern} into a PERL style regular expression.
  
  @param pattern
  regular expression pattern
  @return PERL style regular expression as string