public/channel-buffering

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    <div class="example" id="channel-buffering">
      <h2><a href="./">Go by Example</a>: Channel Buffering</h2>
      
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            <p>By default channels are <em>unbuffered</em>, meaning that they
will only accept sends (<code>chan &lt;-</code>) if there is a
corresponding receive (<code>&lt;- chan</code>) ready to receive the
sent value. <em>Buffered channels</em> accept a limited
number of  values without a corresponding receiver for
those values.</p>

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            <a href="https://go.dev/play/p/3BRCdRnRszb"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
          <pre class="chroma"><code><span class="line"><span class="cl"><span class="kn">package</span> <span class="nx">main</span></span></span></code></pre>
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          <pre class="chroma"><code><span class="line"><span class="cl"><span class="kn">import</span> <span class="s">&#34;fmt&#34;</span></span></span></code></pre>
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          <pre class="chroma"><code><span class="line"><span class="cl"><span class="kd">func</span> <span class="nf">main</span><span class="p">()</span> <span class="p">{</span></span></span></code></pre>
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            <p>Here we <code>make</code> a channel of strings buffering up to
2 values.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="nx">messages</span> <span class="o">:=</span> <span class="nb">make</span><span class="p">(</span><span class="kd">chan</span> <span class="kt">string</span><span class="p">,</span> <span class="mi">2</span><span class="p">)</span></span></span></code></pre>
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            <p>Because this channel is buffered, we can send these
values into the channel without a corresponding
concurrent receive.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&#34;buffered&#34;</span>
</span></span><span class="line"><span class="cl">    <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&#34;channel&#34;</span></span></span></code></pre>
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            <p>Later we can receive these two values as usual.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="o">&lt;-</span><span class="nx">messages</span><span class="p">)</span>
</span></span><span class="line"><span class="cl">    <span class="nx">fmt</span><span class="p">.</span><span class="nf">Println</span><span class="p">(</span><span class="o">&lt;-</span><span class="nx">messages</span><span class="p">)</span>
</span></span><span class="line"><span class="cl"><span class="p">}</span></span></span></code></pre>
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          <pre class="chroma"><code><span class="line"><span class="cl"><span class="gp">$</span> go run channel-buffering.go 
</span></span><span class="line"><span class="cl"><span class="go">buffered
</span></span></span><span class="line"><span class="cl"><span class="go">channel</span></span></span></code></pre>
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      <p class="next">
        Next example: <a href="channel-synchronization">Channel Synchronization</a>.
      </p>
      

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      by <a href="https://markmcgranaghan.com">Mark McGranaghan</a> and <a href="https://eli.thegreenplace.net">Eli Bendersky</a> | <a href="https://github.com/mmcgrana/gobyexample">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
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