How to impose interface?
<p>How I should make sure that classes needed as a one of params to my templated class will have a certain interface? I know that one way is to make in Interface class pure virtual but I would like to avoid it. Is there any other way to do it?  I would like to avoid anything which isn't standard</p>

<pre><code>    //Example  
    template&lt;class SomePolicy&gt;  
    class My
    {
void fnc()const
{
SomePolicy::mustHaveThisInterface();//&lt;--here I have to have  
// this interface in orded to work

}
    };
</code></pre>
