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    <div class="example" id="variables">
      <h2><a href="./">Go by Example</a>: Variables</h2>
      
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            <p>In Go, <em>variables</em> are explicitly declared and used by
the compiler to e.g. check type-correctness of function
calls.</p>

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            <a href="https://go.dev/play/p/N5rWndIliJW"><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><code>var</code> declares 1 or more variables.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="kd">var</span> <span class="nx">a</span> <span class="p">=</span> <span class="s">&#34;initial&#34;</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">a</span><span class="p">)</span></span></span></code></pre>
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            <p>You can declare multiple variables at once.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="kd">var</span> <span class="nx">b</span><span class="p">,</span> <span class="nx">c</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></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">b</span><span class="p">,</span> <span class="nx">c</span><span class="p">)</span></span></span></code></pre>
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            <p>Go will infer the type of initialized variables.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="kd">var</span> <span class="nx">d</span> <span class="p">=</span> <span class="kc">true</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">d</span><span class="p">)</span></span></span></code></pre>
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            <p>Variables declared without a corresponding
initialization are <em>zero-valued</em>. For example, the
zero value for an <code>int</code> is <code>0</code>.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="kd">var</span> <span class="nx">e</span> <span class="kt">int</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">e</span><span class="p">)</span></span></span></code></pre>
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            <p>The <code>:=</code> syntax is shorthand for declaring and
initializing a variable, e.g. for
<code>var f string = &quot;apple&quot;</code> in this case.
This syntax is only available inside functions.</p>

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          <pre class="chroma"><code><span class="line"><span class="cl">    <span class="nx">f</span> <span class="o">:=</span> <span class="s">&#34;apple&#34;</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">f</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 variables.go
</span></span><span class="line"><span class="cl"><span class="go">initial
</span></span></span><span class="line"><span class="cl"><span class="go">1 2
</span></span></span><span class="line"><span class="cl"><span class="go">true
</span></span></span><span class="line"><span class="cl"><span class="go">0
</span></span></span><span class="line"><span class="cl"><span class="go">apple</span></span></span></code></pre>
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        Next example: <a href="constants">Constants</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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