Last active
April 15, 2016 03:48
-
-
Save z5h/41ca436679591b6c3e51 to your computer and use it in GitHub Desktop.
Go here instead: http://package.elm-lang.org/packages/z5h/time-app/
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
module TimeApp ( start, Config, App ) where | |
{-| This module helps you start your application in a typical Elm workflow. | |
It assumes you are following [the Elm Architecture][arch] and using | |
[elm-effects][]. From there it will wire everything up for you! | |
**Be sure to [read the Elm Architecture tutorial][arch] to learn how this all | |
works!** | |
[arch]: https://github.com/evancz/elm-architecture-tutorial | |
[elm-effects]: http://package.elm-lang.org/packages/evancz/elm-effects/latest | |
# Start your Application | |
@docs start, Config, App | |
-} | |
import Html exposing (Html) | |
import Task | |
import Effects exposing (Effects, Never) | |
import Time exposing (Time) | |
{-| The configuration of an app follows the basic model / update / view pattern | |
that you see in every Elm program. | |
The `init` transaction will give you an initial model and create any tasks that | |
are needed on start up. | |
The `update` and `view` fields describe how to step the model and view the | |
model. | |
The `inputs` field is for any external signals you might need. If you need to | |
get values from JavaScript, they will come in through a port as a signal which | |
you can pipe into your app as one of the `inputs`. | |
-} | |
type alias Config model action = | |
{ init : (model, Effects action) | |
, update : action -> Time -> model -> (model, Effects action) | |
, view : Signal.Address action -> model -> Html | |
, inputs : List (Signal.Signal action) | |
} | |
{-| An `App` is made up of a couple signals: | |
* `html` — a signal of `Html` representing the current visual | |
representation of your app. This should be fed into `main`. | |
* `model` — a signal representing the current model. Generally you | |
will not need this one, but it is there just in case. You will know if you | |
need this. | |
* `tasks` — a signal of tasks that need to get run. Your app is going | |
to be producing tasks in response to all sorts of events, so this needs to | |
be hooked up to a `port` to ensure they get run. | |
-} | |
type alias App model = | |
{ html : Signal Html | |
, model : Signal model | |
, tasks : Signal (Task.Task Never ()) | |
} | |
{-| Start an application. It requires a bit of wiring once you have created an | |
`App`. It should pretty much always look like this: | |
app = | |
start { init = init, view = view, update = update, inputs = [] } | |
main = | |
app.html | |
port tasks : Signal (Task.Task Never ()) | |
port tasks = | |
app.tasks | |
So once we start the `App` we feed the HTML into `main` and feed the resulting | |
tasks into a `port` that will run them all. | |
-} | |
start : Config model action -> App model | |
start config = | |
let | |
singleton action = [ action ] | |
-- messages : Signal.Mailbox (List action) | |
messages = | |
Signal.mailbox [] | |
-- address : Signal.Address action | |
address = | |
Signal.forwardTo messages.address singleton | |
-- updateStep : (action, Time) (model, Effects action) -> (model, Effects action) | |
updateStep (action, time) (oldModel, accumulatedEffects) = | |
let | |
(newModel, additionalEffects) = config.update action time oldModel | |
in | |
(newModel, Effects.batch [accumulatedEffects, additionalEffects]) | |
-- update : (Time, (List action)) -> (model, Effects action) -> (model, Effects action) | |
update (time, actions) (model, _) = | |
List.foldl updateStep (model, Effects.none) (List.map (\a -> (a, time)) actions) | |
-- inputs : Signal (List action) | |
inputs = | |
Signal.mergeMany (messages.signal :: List.map (Signal.map singleton) config.inputs) | |
-- inputsWithTime : Signal (Time, (List action)) | |
inputsWithTime = | |
Time.timestamp inputs | |
-- effectsAndModel : Signal (model, Effects action) | |
effectsAndModel = | |
Signal.foldp update config.init inputsWithTime | |
model = | |
Signal.map fst effectsAndModel | |
in | |
{ html = Signal.map (config.view address) model | |
, model = model | |
, tasks = Signal.map (Effects.toTask messages.address << snd) effectsAndModel | |
} |
Awesome, thanks!
Yeah, the signature of TimeApp.start
is different enough from StartApp.start
that I don't know what to do. I haven't used Effects.
My main:
main : Signal Html
main = StartApp.start { model = model, view = view, update = update }
Suggested main:
app = TimeApp.start { init = ?, inputs = ? view = view, update = update }
app = main.html
@ethagnawl @prt2121 @jorgebg @doppioslash @simonewebdesign thanks for the stars. I've published this GIST as an elm package here http://package.elm-lang.org/packages/z5h/time-app/1.0.1/
In case Action and Time are coupled why not use (Action, Time) -> Model -> (Model, Effects Action) signature?
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
@metaraine I had opened an issue (some time ago) in the hopes of adding this to the official start-app. I've received no official response.
https://github.com/evancz/start-app/issues/24
I'll try to add some documentation and publish it before the weekend.