code class="flex name class">
<span>class <span class="ident">Span</span></span>
<span>(</span><span>start, end)</span>
</code></dt>
<dd>
<div class="desc"><p>Class that represents an offset range.</p>
<p>Create a span of length end-start. The end offset must not be less than the start offset and both
the start and end offset must be &gt;= 0.</p>
<p>To allow for a clear a simple definition of all span relations (overlapping and ordering between spans),
we see a span as the interval of real numbers that incl