of the <code>text</code> aesthetic provides a sufficient workaround. Specifically, as Figure <a href="controlling-tooltips.html#fig:text-clever">25.9</a> shows, if one wanted to control a displayed aesthetic value (e.g., <code>y</code>), one could generate a custom string from that variable and supply it to <code>text</code>, then essentially replace <code>text</code> for <code>y</code> in the tooltip:</p>
<div class="sourceCode" id="cb219"><pre class="sourceCode r"><code class="sourceCode r"><span id="cb21