title: Rails ACL Design Question
body: <p>I am working on a legacy rails codebase and need to implement some ACL logic that is not based around standard CRUD operations on objects, but instead around custom logic about what parts of a page are shown to different groups of users.  These page "parts" are not defined by any objects in the database, so my guess is that object-based ACL systems may not be the best fit here.</p>
  
  <p>I currently researching <a href="https://github.com/stffn/declarative_authorization" rel="nofollow">declarative_authorization</a> but haven't yet determined if it can do anything other than object-based permissions.  </p>
  
  <p>This must be a rather common use-case for web applications and I'd prefer not to roll yet another ACL.  Does anyone have a suggestion for a 3rd party library that would work well for this?</p>