 class="anchor" href="#details"></a>Details</h2>

    <p>Important: The object returned by this function behaves like an R6 object,
i.e., within function calls with this object as parameter, it is most likely
that the object will be modified. Therefore it is not necessary to assign
the result of the functions to the same object.</p>

    <h2 class="hasAnchor" id="examples"><a class="anchor" href="#examples"></a>Examples</h2>
    <pre class="examples"><div class='input'><span class='kw'>if</span> <span class