gistfile1.ml

module Event =
  open System.Threading

  let concat (source: IEvent<IEvent<_,_>>) =
   let event = new Event<_>()
   source.Add (Event.listen event.Trigger)
   event.Publish

  let collect f =
    Event.map f >> concat

  let post (context:SynchronizationContext) (sourceEvent: IEvent<IEvent<_,_>>) =
    let event = new Event<_>()
    sourceEvent.Add(fun args ->
                      context.Post(SendOrPostCallback(fun _ -> event.Trigger args), null))
    event.Publish

  let sample interval (sourceEvent:IEvent<'del, 'a>) =
    let event = new Event<_>()
    let intervalCount = ref interval
    sourceEvent.Add(fun args ->
                      if !intervalCount > 0 then decr intervalCount
                      else intervalCount := interval; event.Trigger args)
    event.Publish

  let skip n (sourceEvent:IEvent<_,_>) =
    let event = new Event<_>()
    let remaining = ref n
    sourceEvent.Add(fun args -> if !remaining > 0 then decr remaining else event.Trigger args)
    event.Publish

  let skipWhile predicate (sourceEvent:IEvent<_,_>) =
    let event = new Event<_>()
    let ok = ref true
    sourceEvent.Add(fun args -> 
                      if !ok then
                        ok := predicate args
                      else
                        event.Trigger args)
    event.Publish

  let take n (sourceEvent:IEvent<_,_>) =
    let event = new Event<_>()
    let remaining = ref n
    sourceEvent.Add(fun args -> if !remaining > 0 then decr remaining; event.Trigger args)
    event.Publish

  let takeWhile predicate (sourceEvent:IEvent<_,_>) =
    let event = new Event<_>()
    let ok = ref true
    sourceEvent.Add(fun args -> 
                      if !ok then
                        ok := predicate args
                        event.Trigger args)
    event.Publish

  let until (other: IEvent<_,_>) (source: IEvent<_,_>) =
    let event = new Event<_>()
    let ok = ref true
    other .Add(fun _    -> ok := false)
    source.Add(fun args -> if !ok then event.Trigger args)
    event.Publish

  let waitUntil (other: IEvent<_,_>) (source: IEvent<_,_>) =
    let event = new Event<_>()
    let ok = ref false
    other .Add(fun _    -> ok := true)
    source.Add(fun args -> if !ok then event.Trigger args)
    event.Publish