overload-dispatch-expression"><em>overload-dispatch-expression</em></a>,
        only the second form is allowed and fn must be a pointer to function
        or pointer to member function whose <a href="definitions.html#arity">
          arity</a> is the same as A1's <a href=
          "overloads.html#overload-dispatch-expression"><em>maximum
          arity</em></a>.

          <dl>
            <dt><b>Effects:</b> For each prefix <em>P</em> of
            <code>Fn</code>'s sequence of argument types, begin