Method appendTo

java/com/google/re2j/Regexp.java:106–269

(StringBuilder out)

  // appendTo() appends the Perl syntax for |this| regular expression to |out|.
  private void appendTo(StringBuilder out) {
    switch (op) {
      case NO_MATCH:
        out.append("[^\\x00-\\x{10FFFF}]");
        break;
      case EMPTY_MATCH:
        out.append("(?:)");
        break;
      case STAR:
      case PLUS:
      case QUEST:
      case REPEAT:
        {
          Regexp sub = subs[0];
          if (sub.op.ordinal() > Op.CAPTURE.ordinal()
              || (sub.op == Op.LITERAL && sub.runes.length > 1)) {
            out.append("(?:");
            sub.appendTo(out);
            out.append(')');
          } else {
            sub.appendTo(out);
          }
          switch (op) {
            case STAR:
              out.append('*');
              break;
            case PLUS:
              out.append('+');
              break;
            case QUEST:
              out.append('?');
              break;
            case REPEAT:
              out.append('{').append(min);
              if (min != max) {
                out.append(',');
                if (max >= 0) {
                  out.append(max);
                }
              }
              out.append('}');
              break;
          }
          if ((flags & RE2.NON_GREEDY) != 0) {
            out.append('?');
          }
          break;
        }
      case CONCAT:
        for (Regexp sub : subs) {
          if (sub.op == Op.ALTERNATE) {
            out.append("(?:");
            sub.appendTo(out);
            out.append(')');
          } else {
            sub.appendTo(out);
          }
        }