is carried along to the member part, even if that particular
member is not defined as <code>const</code>. For instance, if the elements
are of type <code>const T *</code>, sorting by <code>T::i</code> is <i>not</i>
specified as <code>member&lt;const T,int,&amp;T::i></code>, but rather as
<code>member&lt;T,const int,&amp;T::i></code>.
</p>

<p>
For practical demonstrations of use of these key extractors, refer to
<a href="../examples.html#example2">example 2</a> and
<a href="../examples.html#example6">exampl