title: ruby `require': cannot load such file
body: <p>I have a directory tree.</p>
  
  <pre><code>- app.rb
  - folder/
    -one.rb
  </code></pre>
  
  <p>app.rb</p>
  
  <pre><code> $:.unshift File.dirname(__FILE__)
   require 'folder/one'
  </code></pre>
  
  <p>When I ran <code>ruby app.rb</code>, I got this error:</p>
  
  <pre><code>`require': cannot load such file -- ./radius/dictionary (LoadError).
  </code></pre>
  
  <p>I don't know why. Please help.</p>