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<ol class="chapter"><li class="chapter-item expanded affix "><a href="u00-intro.html">Golocron</a></li><li class="chapter-item expanded affix "><li class="part-title">The Style Guide</li><li class="chapter-item expanded "><a href="u01-00-introduction.html"><strong aria-hidden="true">1.</strong> Project Layout</a></li><li><ol class="section"><li class="chapter-item expanded "><a href="u01-01-good-and-bad-layout.html"><strong aria-hidden="true">1.1.</strong> Good and Bad Layout</a></li><li class="chapter-item expanded "><a href="u01-02-types-of-layouts.html"><strong aria-hidden="true">1.2.</strong> Types of Layouts</a></li><li class="chapter-item expanded "><a href="u01-03-common.html"><strong aria-hidden="true">1.3.</strong> Common</a></li><li class="chapter-item expanded "><a href="u01-04-library.html"><strong aria-hidden="true">1.4.</strong> Library</a></li><li class="chapter-item expanded "><a href="u01-05-single-application.html"><strong aria-hidden="true">1.5.</strong> Single 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<h3 id="use-simple-branching-in-trivial-cases"><a class="header" href="#use-simple-branching-in-trivial-cases">Use Simple Branching in Trivial Cases</a></h3>
<p>Use simple branching in trivial cases.</p>
<p>A simplest form of cross-platform code is setting a variable within an <code>if</code> or <code>switch</code> statement depending on values of <code>runtime.GOOS</code>, <code>runtime.GOARCH</code> or <code>runtime.Version()</code>.</p>
<p>Such code does not require any build constraints (reminder, build constraints can be expressed as a suffix in the name of a file, or as a build tag). The result depends on the values of the corresponding constants or the returned value of the <code>Version()</code> function, which in turn depend on the system where the program is running and/or version of Go used during the build process.</p>
<p>However, it's tempting to abuse this method. Beware that it is only helpful in very basic cases like choosing the appropriate extension of a file name or something similar. Never implement different <strong>behaviour</strong> based on branching depending on the aforementioned values. This leads to fragile architecture and complicates testing, debugging and maintenance overall.</p>
<p>This method helps to choose what path the execution will follow <strong>at runtime</strong>, but it <em>does not imply</em> conditional compilation. If implementations vary between platforms, and are not available on them at the same time, then builds will be broken.</p>
<p>Essentially, one of the most reasonable uses of this option is to determine and/or report what actual platform the code is <em>running</em> on.</p>
<p>Don't confuse runtime conditions with compile-time conditions.</p>
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