Is this a bug or lack of understanding?

[Martin v. Loewis]

>     struct s {
>         bool operator()(string s1, string s2) {
>             return (s1.size() < s2.size()
>                     || s1 < s2);
>         }
>     };

Shouldn't that be

    struct s {
        bool operator()(string s1, string s2) {
            return (s1.size() < s2.size()
		    or (s1.size() == s2.size() and s1 < s2));
        }
    };

instead?

Regards,
Martin