Method emptyOpContext

java/com/google/re2j/Utils.java:182–202

(int r1, int r2)

  // Passing r2 == -1 indicates that the position is at the end of the text.
  // TODO(adonovan): move to Machine.
  static int emptyOpContext(int r1, int r2) {
    int op = 0;
    if (r1 < 0) {
      op |= EMPTY_BEGIN_TEXT | EMPTY_BEGIN_LINE;
    }
    if (r1 == '\n') {
      op |= EMPTY_BEGIN_LINE;
    }
    if (r2 < 0) {
      op |= EMPTY_END_TEXT | EMPTY_END_LINE;
    }
    if (r2 == '\n') {
      op |= EMPTY_END_LINE;
    }
    if (isWordRune(r1) != isWordRune(r2)) {
      op |= EMPTY_WORD_BOUNDARY;
    } else {
      op |= EMPTY_NO_WORD_BOUNDARY;
    }
    return op;
  }

  private Utils() {} // uninstantiable
}