Rails 3, ActiveRecord, Detecting changes in has_many association
I have the following associations

class User < ActiveRecord::base 
  has_many :memberships
end

What I would like to do is to detect in the users_controller update action that some memberships have been added or removed from the user.memberships.

Any idea or suggestion on how to implement this?

Thanks for any help.
Rails 3, ActiveRecord, Detecting changes in has_many association
===

I have the following associations

class User < ActiveRecord::base 
  has_many :memberships
end

What I would like to do is to detect in the users_controller update action that some memberships have been added or removed from the user.memberships.

Any idea or suggestion on how to implement this?

Thanks for any help.