title: railstutorial where is debug information coming from
body: <p>In chapter 7 I'm getting the following output with </p>
  
  <pre><code>--- !ruby/hash-with-ivars:ActionController::Parameters
  elements:
    controller: static_pages
    action: home
  ivars:
    :@permitted: false
  </code></pre>
  
  <p>could someone explain where the hash-with-ivars is coming from and what  ivars:
        :@permitted: false means?</p>