ass="token plain">    </span><span class="token comment" style="color:#999988;font-style:italic">// 将当前 watcher 添加到 Dep 的订阅者列表中</span><span class="token plain"></span><br></span><span class="token-line" style="color:#393A34"><span class="token plain">    dep</span><span class="token punctuation" style="color:#393A34">.</span><span class="token function" style="color:#d73a49">addSub</span><span class="token punctuation" style="color:#393A34">(</span><span class="token keyword" style