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      <h2><a href="./">Go by Example</a>: Channels</h2>
      
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            <p><em>Channels</em> are the pipes that connect concurrent
goroutines. You can send values into channels from one
goroutine and receive those values into another
goroutine.</p>

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            <a href="https://go.dev/play/p/MaLY7AiAkHM"><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>Create a new channel with <code>make(chan val-type)</code>.
Channels are typed by the values they convey.</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></span></code></pre>
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            <p><em>Send</em> a value into a channel using the <code>channel &lt;-</code>
syntax. Here we send <code>&quot;ping&quot;</code>  to the <code>messages</code>
channel we made above, from a new goroutine.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="k">go</span> <span class="kd">func</span><span class="p">()</span> <span class="p">{</span> <span class="nx">messages</span> <span class="o">&lt;-</span> <span class="s">&#34;ping&#34;</span> <span class="p">}()</span></span></span></code></pre>
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            <p>The <code>&lt;-channel</code> syntax <em>receives</em> a value from the
channel. Here we&rsquo;ll receive the <code>&quot;ping&quot;</code> message
we sent above and print it out.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="nx">msg</span> <span class="o">:=</span> <span class="o">&lt;-</span><span class="nx">messages</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="nx">msg</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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            <p>When we run the program the <code>&quot;ping&quot;</code> message is
successfully passed from one goroutine to another via
our channel.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl"><span class="gp">$</span> go run channels.go 
</span></span><span class="line"><span class="cl"><span class="go">ping</span></span></span></code></pre>
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            <p>By default sends and receives block until both the
sender and receiver are ready. This property allowed
us to wait at the end of our program for the <code>&quot;ping&quot;</code>
message without having to use any other synchronization.</p>

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      <p class="next">
        Next example: <a href="channel-buffering">Channel Buffering</a>.
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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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