I'd be amazed if this actually broke any apps. Shocked! But, better safe than sorry.
The effect handler for :db has changed: if the new value provided tests
identical? to the existing value within app-db, then app-db is not reset!.
Previously, app-db was always reset! irrespective,
which potentially caused Layer 2 subscriptions to run unnecessarily. So this is a tiny
efficiency change in this edge case, and it results in behaviour that better matches
Minor Fixes and Improvements
#400 Improve error message when a registered cofx can't be found
The effect handler for :dispatch-n will now ignore nils. See checkin
reg-sub enforces using :<- to indicate subscription inputs. Previously any keyword would have worked here. While using anything other than :<- was undefined behaviour previously, this could possibly break some code when upgrading. Thanks to @Sohalt#336.
re-frame.interceptor/update-coeffect has been fixed. #328