erties on Backbone models
to functions that depend on them.</p>
<p>One of the most common patterns when using Backbone is the following:</p>
<ul>
<li>make a function that depends on several things in a Backbone model</li>
<li>extract values from the model into local variables</li>
<li>add an if statement to check if all properties are defined before using them</li>
<li>add change listeners for properties in the model so the function is called when those properties change</li>
<li>call the function once for 