quote>
<b>Requires:</b> <code>0 &lt;= N &lt; I</code>.<br>
<b>Effects:</b> Returns a reference to the
<code>nth_index&lt;N>::type</code> index held by <code>*this</code>.<br>
<b>Complexity:</b> Constant.<br>
</blockquote>

<code>template&lt;int N> const typename nth_index&lt;N>::type&amp; get()const noexcept;</code>

<blockquote>
<b>Requires:</b> <code>0 &lt;= N &lt; I</code>.<br>
<b>Effects:</b> Returns a <code>const</code> reference to the
<code>nth_index&lt;N>::type</code> index held by <code>*this</code