n> <span class="identifier">pi</span> <span class="special">=</span> <span class="identifier">M_PI</span> <span class="special">;</span>

<span class="comment">// A 'floating' numeric type with a whole numeric value.</span>
<span class="comment">// NOTE: numeric values are typed valued, hence, they are, for instance,</span>
<span class="comment">// integer or floating, despite the value itself being whole or including</span>
<span class="comment">// a fractional part.</span>
<span class="keyword">double</sp