title: Uninitialized constant Admin::Admin
body: <p>Using Ruby: <code>2.3.1p112</code> and Rails: <code>3.2.12</code>
  <br><br> </p>
  
  <p>I'm trying call a demo method in my controller. So, in my <code>_form.html.erb</code> I have:</p>
  
  <pre><code>&lt;%= link_to 'Demo', "/admin/clinics/"+@clinic.id.to_s+"/demo" %&gt;
  </code></pre>
  
  <p>In my <code>routes.rb</code>:</p>
  
  <pre><code>match "/admin" =&gt; "admin#index", :as =&gt; :admin
  
  namespace :admin do
      resources :admin_users
      resources :health_plan_tables
      resources :health_aid_tables
      resources :clients
      resources :clinics
      resources :specialties
      resources :qualifications
      resources :profissionals
      resources :addresses
      resources :documents
      resources :banners
      root :to =&gt; 'banners#index'
      get 'logout' =&gt; 'devise/sessions#destroy'
  
      get 'clinics/:id/demo', to: 'admin/clinics#demo', as: 'demo'
  end
  </code></pre>
  
  <p>My <code>clinics_controller.rb</code> is inside the folder <code>controllers/admin</code>, and I just have:</p>
  
  <pre><code>def demo
      print "hello"
  end 
  </code></pre>
  
  <p>So, when I click on link, error message appears <code>Uninitialized constant Admin::Admin</code>.
  Any ideia how to fix it?</p>