title: Sprockets::CircularDependencyError in Store#index
body: <p><strong>I am following the manual Agile Web Development with Rails 4th edition and I have a problem with sprocket css in rails 3.1.</strong></p>
  
  <p>The code css is:</p>
  
  <p><a href="http://media.pragprog.com/titles/rails4/code/rails31/depot_e/app/assets/stylesheets/application.css.scss" rel="noreferrer">http://media.pragprog.com/titles/rails4/code/rails31/depot_e/app/assets/stylesheets/application.css.scss</a></p>
  
  <p><strong>If I modify the css code of app/assets/stylesheets/aplication.css.scss I catch the next error:</strong></p>
  
  <pre><code>Sprockets::CircularDependencyError in Store#index
  
  Showing /home/ubuntu/Desktop/Depot/app/views/layouts/application.html.erb where line #5 raised:
  
  /home/ubuntu/Desktop/Depot/app/assets/stylesheets/application.css.scss has already been required
  Extracted source (around line #5):
  
  2: &lt;html&gt;
  3: &lt;head&gt;
  4:   &lt;title&gt;Pragprog Books Online Store&lt;/title&gt;
  5: &lt;%= stylesheet_link_tag "application" %&gt;
  6: &lt;%= javascript_include_tag "application" %&gt;
  7: &lt;%= csrf_meta_tag %&gt;
  8: &lt;/head&gt;
  Rails.root: /home/ubuntu/Desktop/Depot
  
  Application Trace | Framework Trace | Full Trace
  app/views/layouts/application.html.erb:5:in`_app_views_layouts_application_html_erb___1008723970_81658620'
  </code></pre>
  
  <p>I dont understand why if I modify a margin value or a padding value in aplication.css.scss for example I get this error.</p>
  
  <p>Thank you very much.</p>