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<title>Go в примерах: If/Else</title>
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<h2><a href="./">Go в примерах</a>: If/Else</h2>
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<p>Условные операторы <code>if</code> и<code>else</code> в Go
выглядят достаточно стандартно</p>
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<a href="http://play.golang.org/p/DprUWlg26IL" target="_blank"><img title="Run code" src="play.png" class="run" /></a><img title="Copy code" src="clipboard.png" class="copy" />
<div class="highlight"><pre><span class="kn">package</span> <span class="nx">main</span>
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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>
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<p>Стандартное использование</p>
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<div class="highlight"><pre> <span class="k">if</span> <span class="mi">7</span><span class="o">%</span><span class="mi">2</span> <span class="o">==</span> <span class="mi">0</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="s">&quot;7 is even&quot;</span><span class="p">)</span>
<span class="p">}</span> <span class="k">else</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="s">&quot;7 is odd&quot;</span><span class="p">)</span>
<span class="p">}</span>
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<p>Вы можете использовать блоке <code>if</code> без блока <code>else</code>.</p>
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<div class="highlight"><pre> <span class="k">if</span> <span class="mi">8</span><span class="o">%</span><span class="mi">4</span> <span class="o">==</span> <span class="mi">0</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="s">&quot;8 is divisible by 4&quot;</span><span class="p">)</span>
<span class="p">}</span>
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<p>Присваивание переменной может происходить до условия.
Любые определенные значения будут доступны в
последующих ветках</p>
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<div class="highlight"><pre> <span class="k">if</span> <span class="nx">num</span> <span class="o">:=</span> <span class="mi">9</span><span class="p">;</span> <span class="nx">num</span> <span class="p">&lt;</span> <span class="mi">0</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">num</span><span class="p">,</span> <span class="s">&quot;is negative&quot;</span><span class="p">)</span>
<span class="p">}</span> <span class="k">else</span> <span class="k">if</span> <span class="nx">num</span> <span class="p">&lt;</span> <span class="mi">10</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">num</span><span class="p">,</span> <span class="s">&quot;has 1 digit&quot;</span><span class="p">)</span>
<span class="p">}</span> <span class="k">else</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">num</span><span class="p">,</span> <span class="s">&quot;has multiple digits&quot;</span><span class="p">)</span>
<span class="p">}</span>
<span class="p">}</span>
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<p>Имейте ввиду, что в Go не надо использовать скобки в условии,
но блок необходимо заключать в фигурные скобки</p>
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<div class="highlight"><pre><span class="gp">$</span> go run <span class="k">if</span>-else.go
<span class="go">7 is odd</span>
<span class="go">8 is divisible by 4</span>
<span class="go">9 has 1 digit</span>
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<p>В Go нет <a href="http://en.wikipedia.org/wiki/%3F:">тернарного if</a>,
поэтому вам нужно использовать полный оператор if
даже для базовых условий.</p>
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<p class="next">
Следующий пример: <a href="switch">Switch</a>.
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<p class="footer">
by <a href="https://markmcgranaghan.com">Mark McGranaghan</a> | <a href="https://github.com/mmcgrana/gobyexample/blob/master/examples/if-else">source</a> | <a href="https://github.com/mmcgrana/gobyexample#license">license</a>
<br/>
переведено Nick S. | <a href="https://github.com/badkaktus/gobyexample">исходники</a>
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