1.1 --- a/src/include/invalid.h	Mon Apr 26 10:35:36 2004 +0000
     1.2 +++ b/src/include/invalid.h	Mon Apr 26 11:11:55 2004 +0000
     1.3 @@ -12,7 +12,12 @@
     1.4    
     1.5    /// See \ref INVALID, how to use it.
     1.6    
     1.7 -  struct Invalid {};
     1.8 +  struct Invalid {
     1.9 +  public:
    1.10 +    bool operator==(Invalid) { return true;  }
    1.11 +    bool operator!=(Invalid) { return false; }
    1.12 +    bool operator< (Invalid) { return false; }
    1.13 +  };
    1.14    
    1.15    /// Invalid iterators.
    1.16