tocol SetAlgebraType</code></div>

<div class="discussion comment">
    <p>A generalized set whose distinct elements are not necessarily
disjoint.</p>

<p>In a model of <code>SetAlgebraType</code>, some elements may subsume other
elements, where</p>

<blockquote><p><code>a</code> <strong>subsumes</strong> <code>b</code> iff <code>([a] as Self).isSupersetOf([b])</code></p></blockquote>

<p>In many models of <code>SetAlgebraType</code> such as <code>Set&lt;T&gt;</code>, <code>a</code>
<em>subsumes</em> <code>