"keyword">using</span> <span class="keyword">namespace</span> <span class="identifier">boost</span><span class="special">::</span><span class="identifier">safe_numerics</span><span class="special">;</span>

<span class="keyword">void</span> <span class="identifier">f</span><span class="special">(</span><span class="keyword">const</span> <span class="keyword">unsigned</span> <span class="keyword">int</span> <span class="special">&amp;</span> <span class="identifier">x</span><span class="special">,</span> <sp