It's just typo, but (yes it's confusing) it work the same.
Let me explain: the name of Transition like 'INCREMENT' or 'DECREMENT' in this example have same "endpoint" -
Counter itself. So in case like this there is no difference
what Transition use, payload do all job (count + 1 or count - 1). So it's only important for debug (like action name in Redux).
Let me explain: the name of Transition like 'INCREMENT' or 'DECREMENT' in this example have same "endpoint" - Counter itself. So in case like this there is no difference what Transition use, payload do all job (count + 1 or count - 1). So it's only important for debug (like action name in Redux).