See also @jckarter's draft for property behaviors (https://gist.github.com/jckarter/f3d392cf183c6b2b2ac3 https://gist.github.com/jckarter/f3d392cf183c6b2b2ac3),

See also @jckarter's draft for property behaviors (https://gist.github.com/jckarter/f3d392cf183c6b2b2ac3 https://gist.github.com/jckarter/f3d392cf183c6b2b2ac3), which also covers property observers.