 has some value</p>



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          <code onmouseout="hideTip(event, '589', 589)" onmouseover="showTip(event, '589', 589)">
            appendIfTrue p s builder
          </code>
          <div class="tip" id="589">
            <strong>Signature:</strong> p:bool -&gt; s:string -&gt; builder:StringBuilder -&gt; StringBuilder<br />
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            <a href="https://github.com/f