きます:</p>

<span class='rusttest'>fn main() {
    #[cfg(target_os = &quot;macos&quot;)]
mod macos_only {
}
}</span><pre class='rust rust-example-rendered'>
<span class='attribute'>#[<span class='ident'>cfg</span>(<span class='ident'>target_os</span> <span class='op'>=</span> <span class='string'>&quot;macos&quot;</span>)]</span>
<span class='kw'>mod</span> <span class='ident'>macos_only</span> {</pre>

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