s="c1"></span>  <span class="c1">// whose completion handler is void(result_type)
</span><span class="c1"></span>  <span class="k">using</span> <span class="n">result_type_completion_handler_type</span> <span class="o">=</span>  <span class="c1">//
</span><span class="c1"></span>  <span class="k">typename</span> <span class="n">_base</span><span class="o">::</span><span class="n">completion_handler_type</span><span class="p">;</span>
</code></pre></div><a href="https://github.com/boostorg/outcome/tree/maste