I have a template that I instantiate with a type that has to be
<div>nullary callable, so</div><div><br></div><div><font class="Apple-style-span" face="&#39;courier new&#39;, monospace">template &lt;typename NullaryCallable&gt; struct X { /*....*/ };</font></div><div><br></div><div>I&#39;d like to be a good boy scout here, so I should constrain the</div>

<div>template parameter, so</div><div><br></div><div><font class="Apple-style-span" face="&#39;courier new&#39;, monospace">template &lt;typename NullaryCallablle&gt; struct X</font></div><div><font class="Apple-style-span" face="&#39;courier new&#39;, monospace">{</font></div>

<div><font class="Apple-style-span" face="&#39;courier new&#39;, monospace">    BOOST_CONCEPT_ASSERT(( Generator&lt;NullaryCallable, void&gt; ));</font></div><div><font class="Apple-style-span" face="&#39;courier new&#39;, monospace">    // ...</font></div>

<div><font class="Apple-style-span" face="&#39;courier new&#39;, monospace">};</font></div><div><br></div><div>However, that constrains it to be nullary callable and returning void, and</div><div>I&#39;d prefer to avoid the void condition.</div>

<div><br></div><div>Is all that sensible, true, and fixable?</div><div><br></div><div>Thx</div><div><br></div><div>- Rob.</div>