"><a href="#cb1-15" aria-hidden="true"></a><span class="kw">dim</span>(flights)</span>
<span id="cb1-16"><a href="#cb1-16" aria-hidden="true"></a><span class="co"># [1] 253316     11</span></span></code></pre></div>
</div>
<div id="introduction" class="section level2">
<h2>Introduction</h2>
<p>In this vignette, we will</p>
<ol style="list-style-type: decimal">
<li><p>first discuss reference semantics briefly and look at the two different forms in which the <code>:=</code> operator can be used</p></li>
<li><