title: Sinatra and question mark
body: <p>I need to make some methods with Sinatra that should look like:</p>
  
  <blockquote>
    <p>http//:localhost:1234/add?string_to_add</p>
  </blockquote>
  
  <p>But when I declare it like this:</p>
  
  <pre><code>get "/add?:string_to_add" do
  ...
  end
  </code></pre>
  
  <p>it doesn't see the <code>string_to_add</code> param.</p>
  
  <p>How should I declare my method and use this parameter to make things work?</p>