Paperclip attachments with dynamic style sizes from Model

Question

Using Rails 2, I try to separate different, dynamic image sizes trough another Model from the Paperclip-Model. My current approach, using a Proc, looks the following:

<

Answer 1

The solution is simple. instance in my first example Proc is an instance of Paperclip::Attachment. As I want to call a File method, one has to get the calling instance inside the Proc:

Proc.new { |clip| clip.instance.attachment_sizes }

instance represents File-instance in the given example.