class="op">(</span><span class="op">)</span>, <span class="va">x</span><span class="op">)</span>,</span></span>
<span class="r-in"><span>  FUN.VALUE <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/character.html" class="external-link">character</a></span><span class="op">(</span><span class="fl">1</span><span class="op">)</span>, USE.NAMES <span class="op">=</span> <span class="cn">TRUE</span></span></span>
<span class="r-in"><span><span class="op">)</span></span></span>
<span cla