Lodash: Filter array of objects and check if not null
<p>I just started using lodash and have this array of objects, where one of the properties either has an integer or is null. I know how to filter the array for items that are null, but how do I check if it's not null?</p>

<p>Let's say I have something like this:</p>

<pre><code>var users = [
    { 'user': 'barney', 'default': 1 },
    { 'user': 'dino', 'default': 0 },
    { 'user': 'wilma', 'default': 1 },
    { 'user': 'fred',   'default': null }
];
</code></pre>

<p>And then I want something like:</p>

<pre><code>var notNullDefault = _.filter(sourceData, ['is_default', ! null ]); // objects with names barney, dino, wilma
var nullDefault = _.filter(sourceData, ['is_default', null ]); // object with name fred
</code></pre>

<p>Again, I'm new to lodash, so maybe there's a better way to accomplish this too.</p>

<p>Thanks in advance.</p>