<span class="o">&amp;</span><span class="p">,</span> <span class="k">const</span> <span class="n">difference_type</span><span class="o">&amp;</span><span class="p">);</span>
  <span class="n">Loc</span> <span class="k">operator</span><span class="o">-</span><span class="p">(</span><span class="k">const</span> <span class="n">Loc</span><span class="o">&amp;</span><span class="p">,</span> <span class="k">const</span> <span class="n">difference_type</span><span class="o">&amp;</span><span class="p">);</span>

