ay could also be created by explicitly declaring an <code class="literal">extent_gen</code> 
object locally,, but the global object makes this declaration unnecessary.  
</p>
</div>
<div class="sect3">
<div class="titlepage"><div><div><h4 class="title">
<a name="indices"></a><code class="literal">indices</code>
</h4></div></div></div>
<pre class="programlisting">
namespace boost {
  multi_array_base::index_gen  indices;
}
</pre>
<p>The MultiArray concept specifies an
<code class="literal">index_gen</code> a