static PatternSyntaxException wrapPatternSyntaxException(PatternSyntaxException e) {
  if (e == null) null;
  S pat = e.getPattern();
  int i = e.getIndex();
  ret new RuntimeException("Regular expression error between " + multiLineQuote(substring(pat, 0, i)) + " and " + multiLineQuote(substring(pat, i)), e);
}