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docs/javascript/Reference/Global_Objects/WeakSet/clear.html

@@ -2,10 +2,10 @@
 <div> <div class="blockIndicator obsolete obsoleteHeader"><p><strong><span class="icon-only-inline" title="This is an obsolete API and is no longer guaranteed to work."><i class="icon-trash"> </i></span> 已废弃</strong><br/>This feature is obsolete. Although it may still work in some browsers, its use is discouraged since it could be removed at any time. Try to avoid using it.</p></div></div>
 <p><code><strong>clear()</strong></code> 方法用于删除 <code>WeakSet</code> 对象的所有元素，但是已经不是 ECMAScript 的一部分了。</p>
 <h2 id="语法">语法</h2>
-<pre class="syntaxbox"><em>ws</em>.clear();</pre>
+<pre><code class="language-javascript"><em>ws</em>.clear();</code></pre>
 <h2 id="示例">示例</h2>
 <h3 id="使用_clear方法">使用 <code>clear方法</code></h3>
-<pre class="brush: js example-bad">var ws = new WeakSet();
+<pre><code class="language-js example-bad">var ws = new WeakSet();
 
 ws.add(window);
 ws.has(window);  // true
@@ -13,7 +13,7 @@ ws.has(window);  // true
 ws.clear();
 
 ws.has(window); // false
-</pre>
+</code></pre>
 <h2 id="规范">规范</h2>
 <p>没有规范或草案。该方法原本计划包括在 ECMAScript 6，但是在草案 revision 28 (October 14, 2014) 被抛弃了。浏览器原先的实现不久后也被移除了，它从来不是标准的一分子。</p>
 <h2 id="浏览器支持">浏览器支持</h2>