span class="o">::</span><span class="kt">ptrdiff_t</span><span class="o">&gt;</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span><span class="mi">1</span><span class="p">);</span><span class="c1">// move to (10,24)</span>
<span class="o">*</span><span class="n">loc</span><span class="o">=</span><span class="p">(</span><span class="n">loc</span><span class="p">(</span><span class="mi">0</span><span class="p">,</span><span class="o">-</span><span class="mi">1</span><span class="p">