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variadic-functions.html
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<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>Go by Example 中文版: 变参函数</title>
<link rel=stylesheet href="site.css">
</head>
<script>
onkeydown = (e) => {
if (e.key == "ArrowLeft") {
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window.location.href = 'closures';
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<body>
<div class="example" id="variadic-functions">
<h2><a href="./">Go by Example 中文版</a>: 变参函数</h2>
<table>
<tr>
<td class="docs">
<p><a href="https://zh.wikipedia.org/wiki/%E5%8F%AF%E8%AE%8A%E5%8F%83%E6%95%B8%E5%87%BD%E6%95%B8"><em>可变参数函数</em></a>。
在调用时可以传递任意数量的参数。
例如，<code>fmt.Println</code> 就是一个常见的变参函数。</p>
</td>
<td class="code empty leading">
</td>
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<tr>
<td class="docs">
</td>
<td class="code leading">
<a href="https://play.studygolang.com/p/Qsf1Cuqajl6"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
<pre class="chroma"><span class="kn">package</span> <span class="nx">main</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kn">import</span> <span class="s">"fmt"</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>这个函数接受任意数量的 <code>int</code> 作为参数。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="kd">func</span> <span class="nf">sum</span><span class="p">(</span><span class="nx">nums</span> <span class="o">...</span><span class="kt">int</span><span class="p">)</span> <span class="p">{</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Print</span><span class="p">(</span><span class="nx">nums</span><span class="p">,</span> <span class="s">" "</span><span class="p">)</span>
<span class="nx">total</span> <span class="o">:=</span> <span class="mi">0</span>
<span class="k">for</span> <span class="nx">_</span><span class="p">,</span> <span class="nx">num</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">nums</span> <span class="p">{</span>
<span class="nx">total</span> <span class="o">+=</span> <span class="nx">num</span>
<span class="p">}</span>
<span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="nx">total</span><span class="p">)</span>
<span class="p">}</span>
</pre>
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<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="kd">func</span> <span class="nf">main</span><span class="p">()</span> <span class="p">{</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>变参函数使用常规的调用方式，传入独立的参数。</p>
</td>
<td class="code leading">
<pre class="chroma">
<span class="nf">sum</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span>
<span class="nf">sum</span><span class="p">(</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">)</span>
</pre>
</td>
</tr>
<tr>
<td class="docs">
<p>如果你有一个含有多个值的 slice，想把它们作为参数使用，
你需要这样调用 <code>func(slice...)</code>。</p>
</td>
<td class="code">
<pre class="chroma">
<span class="nx">nums</span> <span class="o">:=</span> <span class="p">[]</span><span class="kt">int</span><span class="p">{</span><span class="mi">1</span><span class="p">,</span> <span class="mi">2</span><span class="p">,</span> <span class="mi">3</span><span class="p">,</span> <span class="mi">4</span><span class="p">}</span>
<span class="nf">sum</span><span class="p">(</span><span class="nx">nums</span><span class="o">...</span><span class="p">)</span>
<span class="p">}</span>
</pre>
</td>
</tr>
</table>
<table>
<tr>
<td class="docs">
</td>
<td class="code leading">
<pre class="chroma"><span class="gp">$</span> go run variadic-functions.go
<span class="go">[1 2] 3
</span><span class="go">[1 2 3] 6
</span><span class="go">[1 2 3 4] 10</span></pre>
</td>
</tr>
<tr>
<td class="docs">
<p>接下来我们要看的是 Go 函数的另一个关键特性：闭包。</p>
</td>
<td class="code empty">
</td>
</tr>
</table>
<p class="next">
下一个例子: <a href="closures">闭包</a>
</p>
<p class="footer">
<a href="https://twitter.com/mmcgrana">@mmcgrana</a> 和<a href="https://eli.thegreenplace.net">Eli Bendersky</a>编写 | <a href="https://github.com/gobyexample-cn">gobyexample-cn</a> 翻译 | <a href="https://github.com/gobyexample-cn/gobyexample/issues">反馈</a> | <a href="https://github.com/gobyexample-cn/gobyexample">源码</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a> </p>
</p>
</div>
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