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<a href="#" onmousedown="showPopup(this, 'popup00202');"><img src="seealsolink.png" border="0" alt="" title=""></a> SystemVerilog 3.1a语言参考手册</div>
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11.14 super</div>
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<span style="color: #0000FF">super</span>关键字在一个继承类的内部使用，可以用来引用其父类的成员。当父类成员被继承类成员过载的时候就有必要使用<span style="color: #0000FF">super</span>关键字来访问负类的成员。 </p><div class="Element170">
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<div class="Element13"><div class="Element12" id="code00366"><pre class="Element12"><span style="color: #0000FF">class</span> Packet<span style="color: #800080">;</span> <span style="color: #008000">// 负类</span>
<span style="color: #0000FF">integer</span> value<span style="color: #800080">;</span>
<span style="color: #0000FF">function integer</span> delay<span style="color: #800080">();</span>
delay <span style="color: #800080">=</span> value <span style="color: #800080">*</span> value<span style="color: #800080">;</span>
<span style="color: #0000FF">endfunction</span>
<span style="color: #0000FF">endclass</span>
<span style="color: #0000FF">class</span> LinkedPacket <span style="color: #0000FF">extends</span> Packet<span style="color: #800080">;</span> <span style="color: #008000">// 继承类</span>
<span style="color: #0000FF">integer</span> value<span style="color: #800080">;</span>
<span style="color: #0000FF">function integer</span> delay<span style="color: #800080">();</span>
delay <span style="color: #800080">=</span> <span style="color: #0000FF">super</span><span style="color: #800080">.</span>delay<span style="color: #800080">() +</span> value <span style="color: #800080">*</span> <span style="color: #0000FF">super</span><span style="color: #800080">.</span>value<span style="color: #800080">;</span>
<span style="color: #0000FF">endfunction</span>
<span style="color: #0000FF">endclass</span></pre></div></div>
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成员可以是在上一级声明的成员或者通过类的上一级继承而来。但没有办法到达更高的层次（例如，<span style="color: #0000FF">super</span><span style="color: #800080">.</span><span style="color: #0000FF">super</span><span style="color: #800080">.<i></span>count</i>是不允许使用的）。 </p>
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子类（或继承类）是当前类的扩展。而超类（父类或基类）是扩展到当前类的类，它起始于一个最初的基类。 </p>
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当在<span style="color: #0000FF">new</span>中使用<span style="color: #0000FF">super</span>的时候，<span style="color: #0000FF">super</span><span style="color: #800080">.</span><span style="color: #0000FF">new</span>应该是构造器执行的第一条语句。这是因为，超类在当前类之前被初始化，并且，如果用户代码没有提供一个初始化器，那么编译器会自动地调用<span style="color: #0000FF">super</span><span style="color: #800080">.</span><span style="color: #0000FF">new</span>。</p></div>
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