range-over-channels

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    <div class="example" id="range-over-channels">
      <h2><a href="./">Go by Example</a>: Range over Channels</h2>

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            <p>In a <a href="range">previous</a> example we saw how <code>for</code> and
<code>range</code> provide iteration over basic data structures.
We can also use this syntax to iterate over
values received from a channel.</p>

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	        <a href="http://play.golang.org/p/WN7NNh9tvh"><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>
</pre></div>

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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>We&rsquo;ll iterate over 2 values in the <code>queue</code> channel.</p>

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            <div class="highlight"><pre>    <span class="nx">queue</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 class="nx">queue</span> <span class="o">&lt;-</span> <span class="s">&quot;one&quot;</span>
    <span class="nx">queue</span> <span class="o">&lt;-</span> <span class="s">&quot;two&quot;</span>
    <span class="nb">close</span><span class="p">(</span><span class="nx">queue</span><span class="p">)</span>
</pre></div>

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            <p>This <code>range</code> iterates over each element as it&rsquo;s
received from <code>queue</code>. Because we <code>close</code>d the
channel above, the iteration terminates after
receiving the 2 elements. If we didn&rsquo;t <code>close</code> it
we&rsquo;d block on a 3rd receive in the loop.</p>

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            <div class="highlight"><pre>    <span class="k">for</span> <span class="nx">elem</span> <span class="o">:=</span> <span class="k">range</span> <span class="nx">queue</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="nx">elem</span><span class="p">)</span>
    <span class="p">}</span>
<span class="p">}</span>
</pre></div>

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            <div class="highlight"><pre><span class="gp">$</span> go run range-over-channels.go
<span class="go">one</span>
<span class="go">two</span>
</pre></div>

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            <p>This example also showed that it&rsquo;s possible to close
a non-empty channel but still have the remaining
values be received.</p>

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        Next example: <a href="timers">Timers</a>.
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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/range-over-channels">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
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