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="http://play.golang.org/p/34PVHwO6Bn"><img title="Run code" src="play.png" class="run" /></a>
            <div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
</pre></div>

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            <div class="highlight"><pre><span class="kn">import</span> <span class="s">&quot;fmt&quot;</span>
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            <div class="highlight"><pre><span class="kd">func</span> <span class="nx">main</span><span class="p">()</span> <span class="p">{</span>
</pre></div>

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            <p>Here we <code>make</code> a channel of strings buffering up to
2 values.</p>

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            <div class="highlight"><pre>    <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>
</pre></div>

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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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            <div class="highlight"><pre>    <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&quot;buffered&quot;</span>
    <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&quot;channel&quot;</span>
</pre></div>

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            <p>Later we can receive these two values as usual.</p>

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            <div class="highlight"><pre>    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="o">&lt;-</span><span class="nx">messages</span><span class="p">)</span>
    <span class="nx">fmt</span><span class="p">.</span><span class="nx">Println</span><span class="p">(</span><span class="o">&lt;-</span><span class="nx">messages</span><span class="p">)</span>
<span class="p">}</span>
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            <div class="highlight"><pre><span class="gp">$</span> go run channel-buffering.go
<span class="go">buffered</span>
<span class="go">channel</span>
</pre></div>

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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://twitter.com/mmcgrana">@mmcgrana</a> | <a href="mailto:mmcgrana@gmail.com">feedback</a> | <a href="https://github.com/mmcgrana/gobyexample/blob/master/examples/channel-buffering">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
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