(1) What do you mean by "gone"? Impossible?, or simply not included? (2) Isn't "resuming execution from a historical state" the same thing as importing a state?
On Saturday, November 25, 2017 at 12:39:59 PM UTC-6, Mike MacDonald wrote: > > It still supports most of the old time-travel functionality; the only > thing gone is the ability to resume execution from a historical state. I do > not think this is a technical limitation, but rather a decision made to > simplify the debugging workflow. (Also, import/export is a super valuable > feature for QA.) > > On Saturday, November 25, 2017 at 12:34:49 PM UTC-5, John Bugner wrote: >> >> In Elm 0.17, signals were removed, and subscriptions were added. Evan >> says here ( http://elm-lang.org/blog/farewell-to-frp ): >> >That is all nice, but the big benefit is that Elm is now significantly >> easier to learn and use. >> I agree! Thinking about my program in terms of MVU (model, view, update) >> is easier than trying to put together a signal graph. I'm told that this >> change broke things like back-in-time debugging, but I don't know why. Why >> is it not possible anymore? It seems that subscriptions grew out of this >> successful experiment ( >> https://github.com/evancz/start-app/blob/master/src/StartApp.elm ) to >> find a way to simplify programming with signals. >> >> Let's compare the signatures of the 'Program' types ('Config' in >> StartApp.elm): >> >> from https://github.com/evancz/start-app/blob/master/src/StartApp.elm : >> >type alias Config model action = >> > { init : (model, Effects action) >> > , update : action -> model -> (model, Effects action) >> > , view : Signal.Address action -> model -> Html >> > , inputs : List (Signal.Signal action) >> > } >> from http://package.elm-lang.org/packages/elm-lang/html/2.0.0/Html : >> >type alias : >> > { init : (model, Cmd msg) >> > , update : msg -> model -> (model, Cmd msg) >> > , subscriptions : model -> Sub msg >> > , view : model -> Html msg } >> > } >> > -> Program Never model msg >> >> They look pretty similar! 'init' is the same. 'update' is the same. But >> 'view' and 'subscriptions'/'inputs' are different. 'view' lost a parameter, >> and 'subscriptions' gained a parameter. The magic difference that lost us >> BiT debugging must be in there, right? I recall reading that BiT debugging >> was only possible when the signal graph was static. Wouldn't this >> correspond to 'subscriptions' gaining a parameter? (and thus becoming >> dynamic?) and about 'view', why did it have/need a 'Signal.Address action' >> parameter? >> >> I guess my question is: wouldn't it have been possible to make Elm use >> the MVU model, but still allow BiT debugging? (Basically keep using the >> StartApp package?) If so, why then was FRP abandoned? >> >> -- You received this message because you are subscribed to the Google Groups "Elm Discuss" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
