<!DOCTYPE qhelp PUBLIC
  "-//Semmle//qhelp//EN"
  "qhelp.dtd">
<qhelp>
<overview>
<p>
Elements of array literal expressions that are omitted will be initialized to <code>undefined</code>.
However, such omitted elements are easy to miss and make code hard to read. They should be avoided.
</p>

</overview>
<recommendation>

<p>
Explicitly initialize the array elements to <code>undefined</code>. If you want to create an array
with a specific number of uninitialized elements, use the <code>Array</code> constructor instead.
</p>

</recommendation>
<example>

<p>
The following code snippet initializes <code>a</code> to an array of size ten by using omitted
elements.
</p>

<sample src="examples/EmptyArrayInit.js" />

<p>
This code is clearly hard to read, and should be replaced by the following snippet:
</p>

<sample src="examples/EmptyArrayInitGood.js" />

</example>
<references>


<li>D. Crockford, <i>JavaScript: The Good Parts</i>, Appendix C.6. O'Reilly, 2008.</li>


</references>
</qhelp>