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0 pointsones_and_zeros5y ago0 comments

Sure but how does that work with the provided implementation where all states can only transition to a single state, this is ensured at compile time. What does the code look like that allows a state to transition to one of several other states?

0 comments

skrtskrt5y ago

No Rust, but here's a Python implementation that I have built on top of before: https://github.com/pytransitions/transitions

You add the concept of finite "triggers", where [state i] + [trigger result j] always takes you to [new state](which could be the same state if you want)

Triggers are just functions where anything could be happening - coin flip, API call, but they return one of an enumerated set of results so the machine can always use their result to go to another state.

ones_and_zerosOP5y ago

Ah ok. I don't write Rust either but maybe it'd look like:

  impl State<Running> {
    pub fn next(self, Trigger<Hibernate>) -> State<Hibernate> {
        State { _inner: Hibernate {} }
    }

    pub fn next(self, Trigger<Terminate>) -> State<Terminate> {
        State { _inner: Terminate {} }
    }
  }

imtringued5y ago

Usually you would just call your functions hibernate() and terminate(). That way you can call hibernate() on State<Running> but not on State<Terminated> or State<Hibernate>.

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