ass="st">'</span></span>
<span><span class="st">    SEXP a_point( SEXP x ) {</span></span>
<span><span class="st">      return sfheaders::sfg::sfg_point( x );</span></span>
<span><span class="st">    }</span></span>
<span><span class="st">  '</span></span>
<span>  , plugins <span class="op">=</span> <span class="st">"cpp11"</span></span>
<span>  , depends <span class="op">=</span> <span class="fu"><a href="https://rdrr.io/r/base/c.html" class="external-link">c</a></span><span class="op">(</span><span class=