ChooseEffect

The Choose effect models non-determinism So we can get results, either:

• no results (when using ChooseZero)
• the result for action1 or the result for action b (when using ChoosePlus)

When running this effect we can "collect" the results with any F which has an Alternative instance.

For example if F is List then:

• no results is the empty list
• the result for a or b is List(a, b)

If F is Option then:

• no results is the None
• the result for a or b is Some(a) or Some(b