title: How to sort array of strings with multiple conditions?
body: <p>I have an array of strings which need to be sorted by multiple criteria (two string attributes). However the two sorts need to be sorted in opposite directions. </p>
  
  <p>Example:</p>
  
  <blockquote>
    <p>Array must be sorted by attribute_a in desc order and then within that
    sorted by attribute_b in asc order.</p>
  </blockquote>
  
  <p>I have been using .sort_by! which works fine, however I am just unsure how to implement two criteria sorting in opposite sort directions </p>