Note how the form helper ends by <% end =%> You might get in trouble if you miss that.

 
<h1>Article controller, edit action</h1>
 
 
<%= form_for(@article, :action => resource(@article)) do %>
 
  <p>
    <%= text_field :title, :label => "Title"  %>
  </p>
 
  <p>
    <%= text_field :author, :label => "Author"  %>
  </p>
 
  <p>
    <%= submit "Update" %>
  </p>
<% end =%>
 
<%= link_to 'Show', resource(@article) %> | <%= link_to 'Back', resource(:articles) %>