lib/cancan/model_additions.rb references ActiveSupport::Concern, which is unavailable prior to Rails 3. Upon booting a Rails 2.3 install using CanCan 2.0, I get 'uninitialized constant ActiveSupport::Concern (NameError)'.
Seems to have been introduced with f1cebde.
@ryanb, is CanCan 2.0 intended to continue supporting Rails 2.x?
Thanks for your submission! The ryanb/cancan repository has been inactive since Sep 06, 2013.
Since only Ryan himself has commit permissions, the CanCan project is on a standstill.
CanCan has many open issues, including missing support for Rails 4. To keep CanCan alive, an active fork exists at cancancommunity/cancancan. The new gem is cancancan. More info is available at #994.
If your pull request or issue is still applicable, it would be really appreciated if you resubmit it to CanCanCan.
We hope to see you on the other side!