@Override
    public boolean equals(Object o) {
      if (this == o) return true;
      if (!(o instanceof IndexEntry entry)) return false;
      return exprStart == entry.exprStart &&
             exprIndex == entry.exprIndex &&
             contextStart == entry.contextStart &&
             contextEnd == entry.contextEnd &&
             occurrence.equals(entry.occurrence);
    }
@Override
    public boolean equals(Object o)