title: check if a date falls in the last week using date.js
body: <p>i use <a href="https://github.com/datejs" rel="nofollow">date.js</a> for doing certain date calculations.</p>
  
  <p>i am able to find if the date falls in this week, the following returns true</p>
  
  <pre><code>dateFld.between(Date.monday(), Date.friday())
  </code></pre>
  
  <p>but I want to check if date falls in the previous week.</p>
  
  <p>i am using the following code without luck.</p>
  
  <pre><code>alert(dateFld.between(Date.last().week().monday(), Date.last().week().sunday()));
  </code></pre>
  
  <p>please help.</p>