tc.).</span></div>
<div class="line"><a id="l00044" name="l00044"></a><span class="lineno">   44</span><span class="comment"> * Or initialize via no-arg construction which results in an `null() == true` object.  Copy construction, assignment,</span></div>
<div class="line"><a id="l00045" name="l00045"></a><span class="lineno">   45</span><span class="comment"> * equality, total ordering, and hashing all work as one would expect and essentially the same as on the underlying</span></div>
<div class="line"><a 