Thanks for your input Peter and Larry.<div><br></div><div>Larry, I&#39;m fearful of using unreleased code. Any idea when your package_range_c could become part of an official boost release?</div><div><br></div><div>With that in mind I&#39;m interested in using Peter&#39;s approach (which I&#39;m sure is very similar to the internals of your package_c hey Larry?)</div>


<div><br></div><div>I have 3 questions please.</div><div><br></div><div>1. Please can you give an explanation of what the compiler is actually doing in your make_func_helper() and  make_indexes_...() - This goes beyond my capabilities at the moment, and I&#39;m always looking to improve my knowledge.</div>


<div><br></div><div>2. In attached file &quot;attempt_1.cpp&quot; at Line 44 - I&#39;m getting a compiler error &quot;expected primary-expression before &#39;...&#39; token&quot; which I don&#39;t understand. How would I bind the variadic template arguments in order to create a functor of the form boost::function&lt;void()&gt;? </div>


<div><div><br></div><div><font face="&#39;courier new&#39;, monospace">    void call(Args...)</font></div><div><font face="&#39;courier new&#39;, monospace">    {</font></div>
<div><font face="&#39;courier new&#39;, monospace">        boost::function&lt; void() &gt; bound_fn = boost::bind(f, Args...);</font></div><div><font face="&#39;courier new&#39;, monospace">        bound_fn(); // in effect the bound_fn will be stored in a queue for later envocation by a different thread</font></div>


<div><font face="&#39;courier new&#39;, monospace">    }</font></div></div><div><br></div><div>3. In attached file &quot;attempt_2.cpp&quot; at Line 27, there&#39;s a struct cb_ with a typedef &quot;type&quot; of the member function pointer of the form T::fn(Args...). </div>


<div><br></div><div><font face="&#39;courier new&#39;, monospace">    template&lt; class T, class... Args &gt;</font></div><div><font face="&#39;courier new&#39;, monospace">    struct cb_ { typedef void (T::*type)(Args...); };</font></div>


<div><br></div><div>As far as I can see, this is of the same form as Peter&#39;s void (T::*pm)(Args...) member function pointer is it not? How come the compiler can&#39;t match &amp;X::f with  typename cb_&lt;T, Args...&gt;::type?</div>


<div><br></div><div>TIA</div><div>Steve</div>