"c1">// completion function is void(result_type)
</span><span class="c1"></span>      <span class="k">if</span><span class="p">(</span><span class="n">ec</span><span class="p">)</span>
      <span class="p">{</span>
        <span class="c1">// Complete with a failed result
</span><span class="c1"></span>        <span class="n">_handler</span><span class="p">(</span><span class="n">result_type</span><span class="p">(</span><span class="n">outcome</span><span class="o">::</span><span class="n">failure</span><