eno">   41</span>&#160;    {</div>
<div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;        <span class="keyword">using</span> coord_t = value_type;</div>
<div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;    };</div>
<div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;</div>
<div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;    <span class="keyword">static</span> constexpr std::size_t num_dimensio