explicit template parameters.
        </p>
<p>
</p>
<pre class="programlisting"><span class="comment">// Custom point formatter</span>
<span class="keyword">class</span> <span class="identifier">point_formatter</span>
<span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
    <span class="keyword">typedef</span> <span class="keyword">void</span> <span class="identifier">result_type</span><span class="special">;</span>

<span class="keyword">public</span><span class=