 id="comment-insert-85d6bafa09e62d45b6afb5b77af4aa69"><p>Inserts the given element in the set if it is not already present.</p>
<p>If an element equal to <code>newMember</code> is already contained in the set, this
method has no effect. In this example, a new element is inserted into
<code>classDays</code>, a set of days of the week. When an existing element is
inserted, the <code>classDays</code> set does not change.</p>
<pre><code class="language-swift">enum DayOfTheWeek: Int {
    case sunday, monday, tu