module Devise::Controllers::StoreLocation

redirect_to stored_location_for(:user) || root_path

Example:

the given scope. Useful for giving redirect backs after sign up:
Returns and delete (if it's navigational format) the url stored in the session for

def stored_location_for(resource_or_scope)
  session_key = stored_location_key_for(resource_or_scope)
  if is_navigational_format?
    session.delete(session_key)
  else
    session[session_key]
  end
end