Function
Whether this frame is a tap the learner performs, or the result of having performed them all.
The frame to classify
true when the frame carries a control to act on
true
The two are told apart by the target, because that is the actual difference: a step names a control to act on and a result names none. Narrowing on the surface instead would mean re-listing every surface each time a platform gains one.
Whether this frame is a tap the learner performs, or the result of having performed them all.