Release notes for LensKit 0.4

The Git changelog and the list of closed tickets and pull requests provide more information on what has happened, including bugs that have been fixed.

Recommendation and Prediction API

To support more types of recommenders easily, we have changed the way the dynamic recommendation and prediction components and their APIs work (#issue(109), #issue(110)). These changes are backwards-incompatible; client code and implementations need to be updated for 0.4.

Incompatible data structure changes

To clean up APIs, we made a couple notable incompatible changes to layout and data structures. These are all compile errors; no subtle behavior changes that the compiler won’t catch here.

Other Changes