_up.html">set_up</a></code> to change the default value of <code>up</code> within the function.</p></dd>


<dt>msg</dt>
<dd><p>A character vector, default is <code>NULL</code>. If provided, this message will be displayed right under the error message. This is mostly useful when the text contains formatting because the function <code><a href="https://rdrr.io/r/base/stop.html" class="external-link">stop</a></code> used to send the error message erases any formatting.</p></dd>


<dt>envir</dt>
<dd><p>An enviro