defining a hash set with a compare function
<p>I am trying to do a very simple task of defining a new type of hash set which has a compare function as well. </p>

<pre><code>using namespace std;
#include &lt;iostream&gt;
#include &lt;ext/hash_set&gt;
#include &lt;hash_set&gt;
#include &lt;functional&gt;
#include &lt;hash_compare&gt;
typedef __gnu_cxx::hash_set&lt;int, hash_compare&lt;int, less&lt;int&gt; &gt; &gt; hashcomp;

int main(int argc, char *  const argv[]) {

}
</code></pre>

<p>Error: hash_compare is not defined   (line 7)<br>
Error: expected unqualified-id before ">" token    (line 7)<br>
Error: template argument 2 is invalid.     (line 7) </p>
