Method isCharClass

java/com/google/re2j/Parser.java:1184–1189

(Regexp re)

  // can this be represented as a character class?
  // single-rune literal string, char class, ., and .|\n.
  private static boolean isCharClass(Regexp re) {
    return ((re.op == Regexp.Op.LITERAL && re.runes.length == 1)
        || re.op == Regexp.Op.CHAR_CLASS
        || re.op == Regexp.Op.ANY_CHAR_NOT_NL
        || re.op == Regexp.Op.ANY_CHAR);
  }

  // does re match r?
  private static boolean matchRune(Regexp re, int r) {