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                  <pre class="highlight swift"><code><span class="kd">@available(iOS 13.0, macOS 10.15, tvOS 13.0, watchOS 6.0, *)</span>
<span class="kd">struct</span> <span class="kt">WidthPreference</span> <span class="p">:</span> <span class="kt">PreferenceKey</span></code></pre>

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            <p>Collects width of all the cells, with reduce takes the