Metro "Hello World" JavaScript, but in CoffeeScript

default.coffee

# Blank Metro Template, but in CoffeeScript
# Just a dumb rewrite of the default.js in 
# http://msdn.microsoft.com/en-us/library/windows/apps/hh986964.aspx

buttonClickHandler = (eventInfo) ->
    userName = document.getElementById("nameInput").value
    greetingString = "Hello, #{userName}!"; # oh yeah, CS does string interpolation
    document.getElementById("greetingOutput").innerText = greetingString

app = WinJS.Application
activation = Windows.ApplicationModel.Activation
WinJS.strictProcessing()

app.onactivated = (args) ->
    if args.detail.kind == activation.ActivationKind.launch
        # TODO: This application has been newly launched. Initialize
        # your application here.
    else
        # TODO: This application has been reactivated from suspension.
        # Restore application state here.
    args.setPromise WinJS.UI.processAll()
    helloButton = document.getElementById("helloButton")
    helloButton.addEventListener("click", buttonClickHandler, false)

app.oncheckpoint = (args) ->
    # TODO: This application is about to be suspended. Save any state
    # that needs to persist across suspensions here. You might use the
    # WinJS.Application.sessionState object, which is automatically
    # saved and restored across suspension. If you need to complete an
    # asynchronous operation before your application is suspended, call
    # args.setPromise()

app.start()

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