>Future</span><span class="o">&lt;</span><span class="kt">int</span><span class="o">&gt;</span><span class="w"> </span><span class="n">fu</span><span class="w"> </span><span class="o">=</span><span class="w"> </span><span class="n">executor</span><span class="p">.</span><span class="n">async</span><span class="p">([](){</span>
<span class="w">  </span><span class="k">return</span><span class="w"> </span><span class="mi">1</span><span class="p">;</span>
<span class="p">});</span>
<span class="n">fu</span><sp