 in place. Many functions in the Janet core
library will also create arrays, such as <code class="mendoza-code">map</code>, <code class="mendoza-code">filter</code>, and
<code class="mendoza-code">interpose</code>.
</p>
<h2 id="Array-length">Array length
</h2>
<p>The length of an array is the number of elements in the array. The last element
of the array is therefore at index length - 1. To get the length of an array,
use the <code class="mendoza-code">(length x)</code> function.
</p>
<h2 id="Creating-array