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<li><a class="reference internal" href="#">if - conditionally execute a command</a><ul>
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<section id="if-conditionally-execute-a-command">
<h1>if - conditionally execute a command<a class="headerlink" href="#if-conditionally-execute-a-command" title="Link to this heading">¶</a></h1>
<section id="synopsis">
<h2>Synopsis<a class="headerlink" href="#synopsis" title="Link to this heading">¶</a></h2>
<div class="highlight-fish-synopsis notranslate"><div class="highlight"><pre><span></span><span class="nf">if</span><span class="w"> </span><span class="no">CONDITION</span><span class="p">;</span><span class="w"> </span><span class="nf">COMMANDS_TRUE</span><span class="w"> </span><span class="g g-Other">...</span><span class="p">;</span>
<span class="g g-Other">[</span><span class="nf">else</span><span class="w"> </span><span class="nf">if</span><span class="w"> </span><span class="no">CONDITION2</span><span class="p">;</span><span class="w"> </span><span class="nf">COMMANDS_TRUE2</span><span class="w"> </span><span class="g g-Other">...</span><span class="p">;</span><span class="g g-Other">]</span>
<span class="g g-Other">[</span><span class="nf">else</span><span class="p">;</span><span class="w"> </span><span class="nf">COMMANDS_FALSE</span><span class="w"> </span><span class="g g-Other">...</span><span class="p">;</span><span class="g g-Other">]</span>
<span class="nf">end</span>
</pre></div>
</div>
</section>
<section id="description">
<h2>Description<a class="headerlink" href="#description" title="Link to this heading">¶</a></h2>
<p><code class="docutils literal notranslate"><span class="pre">if</span></code> will execute the command <code class="docutils literal notranslate"><span class="pre">CONDITION</span></code>. If the condition’s exit status is 0, the commands <code class="docutils literal notranslate"><span class="pre">COMMANDS_TRUE</span></code> will execute. If the exit status is not 0 and <a class="reference internal" href="else.html"><span class="doc">else</span></a> is given, <code class="docutils literal notranslate"><span class="pre">COMMANDS_FALSE</span></code> will be executed.</p>
<p>You can use <a class="reference internal" href="and.html"><span class="doc">and</span></a> or <a class="reference internal" href="or.html"><span class="doc">or</span></a> in the condition. See the second example below.</p>
<p>The exit status of the last foreground command to exit can always be accessed using the <a class="reference internal" href="../language.html#variables-status"><span class="std std-ref">$status</span></a> variable.</p>
<p>The <strong>-h</strong> or <strong>--help</strong> option displays help about using this command.</p>
</section>
<section id="example">
<h2>Example<a class="headerlink" href="#example" title="Link to this heading">¶</a></h2>
<p>The following code will print <code class="docutils literal notranslate"><span class="pre">foo.txt</span> <span class="pre">exists</span></code> if the file foo.txt exists and is a regular file, otherwise it will print <code class="docutils literal notranslate"><span class="pre">bar.txt</span> <span class="pre">exists</span></code> if the file bar.txt exists and is a regular file, otherwise it will print <code class="docutils literal notranslate"><span class="pre">foo.txt</span> <span class="pre">and</span> <span class="pre">bar.txt</span> <span class="pre">do</span> <span class="pre">not</span> <span class="pre">exist</span></code>.</p>
<div class="highlight-fish-docs-samples notranslate"><div class="highlight"><pre><span></span><span class="nf">if</span><span class="w"> </span><span class="nf">test</span><span class="w"> </span><span class="no">-f</span><span class="w"> </span><span class="no">foo.txt</span>
<span class="w"> </span><span class="nf">echo</span><span class="w"> </span><span class="no">foo.txt</span><span class="w"> </span><span class="no">exists</span>
<span class="nf">else</span><span class="w"> </span><span class="nf">if</span><span class="w"> </span><span class="nf">test</span><span class="w"> </span><span class="no">-f</span><span class="w"> </span><span class="no">bar.txt</span>
<span class="w"> </span><span class="nf">echo</span><span class="w"> </span><span class="no">bar.txt</span><span class="w"> </span><span class="no">exists</span>
<span class="nf">else</span>
<span class="w"> </span><span class="nf">echo</span><span class="w"> </span><span class="no">foo.txt</span><span class="w"> </span><span class="no">and</span><span class="w"> </span><span class="no">bar.txt</span><span class="w"> </span><span class="no">do</span><span class="w"> </span><span class="no">not</span><span class="w"> </span><span class="no">exist</span>
<span class="nf">end</span>
</pre></div>
</div>
<p>The following code will print “foo.txt exists and is readable” if foo.txt is a regular file and readable</p>
<div class="highlight-fish-docs-samples notranslate"><div class="highlight"><pre><span></span><span class="nf">if</span><span class="w"> </span><span class="nf">test</span><span class="w"> </span><span class="no">-f</span><span class="w"> </span><span class="no">foo.txt</span>
<span class="w"> </span><span class="o">and</span><span class="w"> </span><span class="nf">test</span><span class="w"> </span><span class="no">-r</span><span class="w"> </span><span class="no">foo.txt</span>
<span class="w"> </span><span class="nf">echo</span><span class="w"> </span><span class="s2">"foo.txt exists and is readable"</span>
<span class="nf">end</span>
</pre></div>
</div>
</section>
<section id="see-also">
<h2>See also<a class="headerlink" href="#see-also" title="Link to this heading">¶</a></h2>
<p><code class="docutils literal notranslate"><span class="pre">if</span></code> is only as useful as the command used as the condition.</p>
<p>Fish ships a few:</p>
<ul class="simple">
<li><p><a class="reference internal" href="test.html"><span class="doc">test - perform tests on files and text</span></a> can compare numbers, strings and check paths</p></li>
<li><p><a class="reference internal" href="string.html"><span class="doc">string - manipulate strings</span></a> can perform string operations including wildcard and regular expression matches</p></li>
<li><p><a class="reference internal" href="path.html"><span class="doc">path - manipulate and check paths</span></a> can check paths for permissions, existence or type</p></li>
<li><p><a class="reference internal" href="contains.html"><span class="doc">contains - test if a word is present in a list</span></a> can check if an element is in a list</p></li>
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