Example of composition with Superscribe in F#

composition.fs

type NameBeginningWith(letter) as this = 
    inherit GraphNode()
        do
            this.ActivationFunction <- fun data segment -> segment.StartsWith(letter)
            this.ActionFunctions.Add(
                "set_param_Name",
                fun data segment -> data.Parameters?Add("Name", segment));
                

type Startup() =
    member x.Configuration(app: Owin.IAppBuilder) =
        let define = OwinRouteEngineFactory.Create();
        app.UseSuperscribeRouter(define).UseSuperscribeHandler(define) |> ignore

        let hello = ConstantNode("hello")

        define.Route(
            hello / NameBeginningWith "p", 
            fun o -> 
                "Hello " + o?Parameters?Name + ", great first letter!" :> obj) |> ignore

        define.Route(
            hello / String "Name", 
            fun o -> 
                "Hello " + o?Parameters?Name :> obj) |> ignore
 
[<assembly: OwinStartup(typeof<Startup>)>]
do ()