seful.</p>

    <h2><a name="usage">Usage</a></h2>

    <h3><a name="two_arg">Two-Argument</a> Template Forms</h3>

    <h4><a name="two_arg_gen">General Considerations</a></h4>

    <p>The arguments to a binary operator commonly have identical types, but
    it is not unusual to want to define operators which combine different
    types. For <a href="#example">example</a>, one might want to multiply a
    mathematical vector by a scalar. The two-argument template forms of the
    arithmetic operator templa