            <pre class="highlight"><code><span class="kd">public</span> <span class="kd">func</span> <span class="n">runOnce</span><span class="o">&lt;</span><span class="kt">T</span><span class="o">&gt;</span><span class="p">(</span><span class="n">_</span> <span class="nv">function</span><span class="p">:</span> <span class="kd">@autoclosure</span> <span class="p">()</span> <span class="o">-&gt;</span> <span class="kt">T</span><span class="p">)</span> <span class="o">-&gt;</span> <span class="kt">T</span>