MailboxProcessor with exception handling

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/// A wrapper for MailboxProcessor that catches all unhandled exceptions
/// and reports them via the 'OnError' event. Otherwise, the API
/// is the same as the API of 'MailboxProcessor'
type HandlingMailbox<'T>(f:HandlingMailbox<'T> -> Async<unit>) as self =
  // Create an event for reporting errors
  let errorEvent = Event<_>()
  // Start standard MailboxProcessor 
  let inbox = new MailboxProcessor<_>(fun inbox -> async {
    // Run the user-provided function & handle exceptions
    try return! f self
    with e -> errorEvent.Trigger(e) })
  /// Triggered when an unhandled exception occurs
  member x.OnError = errorEvent.Publish
  /// Starts the mailbox processor
  member x.Start() = inbox.Start()
  /// Receive a message from the mailbox processor
  member x.Receive() = inbox.Receive()
  /// Post a message to the mailbox processor
  member x.Post(v:'T) = inbox.Post(v)
  /// Start the mailbox processor
  static member Start(f) =
    let mbox = new HandlingMailbox<_>(f)
    mbox.Start()
    mbox

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// The usage is the same as with standard MailboxProcessor
let counter = HandlingMailbox<_>.Start(fun inbox -> async {
  while true do 
    printfn "waiting for data..." 
    let! data = inbox.Receive()
    // Simulate an exception 
    failwith "fail!" })

// Specify callback for unhandled errors & send message to mailbox
counter.OnError.Add(printfn "Exception: %A")
counter.Post(42) 

Multiple items
type HandlingMailbox<'T> =
  new : f:(HandlingMailbox<'T> -> Async<unit>) -> HandlingMailbox<'T>
  member Post : v:'T -> unit
  member Receive : unit -> Async<'T>
  member Start : unit -> unit
  member OnError : IEvent<exn>
  static member Start : f:(HandlingMailbox<'a> -> Async<unit>) -> HandlingMailbox<'a>

Full name: Script.HandlingMailbox<_>


 A wrapper for MailboxProcessor that catches all unhandled exceptions
 and reports them via the 'OnError' event. Otherwise, the API
 is the same as the API of 'MailboxProcessor'

--------------------
new : f:(HandlingMailbox<'T> -> Async<unit>) -> HandlingMailbox<'T>

val f : (HandlingMailbox<'T> -> Async<unit>)

Multiple items
type Async
static member AsBeginEnd : computation:('Arg -> Async<'T>) -> ('Arg * AsyncCallback * obj -> IAsyncResult) * (IAsyncResult -> 'T) * (IAsyncResult -> unit)
static member AwaitEvent : event:IEvent<'Del,'T> * ?cancelAction:(unit -> unit) -> Async<'T> (requires delegate and 'Del :> Delegate)
static member AwaitIAsyncResult : iar:IAsyncResult * ?millisecondsTimeout:int -> Async<bool>
static member AwaitTask : task:Task<'T> -> Async<'T>
static member AwaitWaitHandle : waitHandle:WaitHandle * ?millisecondsTimeout:int -> Async<bool>
static member CancelDefaultToken : unit -> unit
static member Catch : computation:Async<'T> -> Async<Choice<'T,exn>>
static member FromBeginEnd : beginAction:(AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg:'Arg1 * beginAction:('Arg1 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg1:'Arg1 * arg2:'Arg2 * beginAction:('Arg1 * 'Arg2 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromBeginEnd : arg1:'Arg1 * arg2:'Arg2 * arg3:'Arg3 * beginAction:('Arg1 * 'Arg2 * 'Arg3 * AsyncCallback * obj -> IAsyncResult) * endAction:(IAsyncResult -> 'T) * ?cancelAction:(unit -> unit) -> Async<'T>
static member FromContinuations : callback:(('T -> unit) * (exn -> unit) * (OperationCanceledException -> unit) -> unit) -> Async<'T>
static member Ignore : computation:Async<'T> -> Async<unit>
static member OnCancel : interruption:(unit -> unit) -> Async<IDisposable>
static member Parallel : computations:seq<Async<'T>> -> Async<'T []>
static member RunSynchronously : computation:Async<'T> * ?timeout:int * ?cancellationToken:CancellationToken -> 'T
static member Sleep : millisecondsDueTime:int -> Async<unit>
static member Start : computation:Async<unit> * ?cancellationToken:CancellationToken -> unit
static member StartAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions * ?cancellationToken:CancellationToken -> Task<'T>
static member StartChild : computation:Async<'T> * ?millisecondsTimeout:int -> Async<Async<'T>>
static member StartChildAsTask : computation:Async<'T> * ?taskCreationOptions:TaskCreationOptions -> Async<Task<'T>>
static member StartImmediate : computation:Async<unit> * ?cancellationToken:CancellationToken -> unit
static member StartWithContinuations : computation:Async<'T> * continuation:('T -> unit) * exceptionContinuation:(exn -> unit) * cancellationContinuation:(OperationCanceledException -> unit) * ?cancellationToken:CancellationToken -> unit
static member SwitchToContext : syncContext:SynchronizationContext -> Async<unit>
static member SwitchToNewThread : unit -> Async<unit>
static member SwitchToThreadPool : unit -> Async<unit>
static member TryCancelled : computation:Async<'T> * compensation:(OperationCanceledException -> unit) -> Async<'T>
static member CancellationToken : Async<CancellationToken>
static member DefaultCancellationToken : CancellationToken

Full name: Microsoft.FSharp.Control.Async

--------------------
type Async<'T>

Full name: Microsoft.FSharp.Control.Async<_>

type unit = Unit

Full name: Microsoft.FSharp.Core.unit

val self : HandlingMailbox<'T>

val errorEvent : Event<exn>

Multiple items
module Event

from Microsoft.FSharp.Control

--------------------
type Event<'T> =
  new : unit -> Event<'T>
  member Trigger : arg:'T -> unit
  member Publish : IEvent<'T>

Full name: Microsoft.FSharp.Control.Event<_>

--------------------
type Event<'Delegate,'Args (requires delegate and 'Delegate :> Delegate)> =
  new : unit -> Event<'Delegate,'Args>
  member Trigger : sender:obj * args:'Args -> unit
  member Publish : IEvent<'Delegate,'Args>

Full name: Microsoft.FSharp.Control.Event<_,_>

--------------------
new : unit -> Event<'T>

--------------------
new : unit -> Event<'Delegate,'Args>

val inbox : MailboxProcessor<'T>

Multiple items
type MailboxProcessor<'Msg> =
  interface IDisposable
  new : body:(MailboxProcessor<'Msg> -> Async<unit>) * ?cancellationToken:CancellationToken -> MailboxProcessor<'Msg>
  member Post : message:'Msg -> unit
  member PostAndAsyncReply : buildMessage:(AsyncReplyChannel<'Reply> -> 'Msg) * ?timeout:int -> Async<'Reply>
  member PostAndReply : buildMessage:(AsyncReplyChannel<'Reply> -> 'Msg) * ?timeout:int -> 'Reply
  member PostAndTryAsyncReply : buildMessage:(AsyncReplyChannel<'Reply> -> 'Msg) * ?timeout:int -> Async<'Reply option>
  member Receive : ?timeout:int -> Async<'Msg>
  member Scan : scanner:('Msg -> Async<'T> option) * ?timeout:int -> Async<'T>
  member Start : unit -> unit
  member TryPostAndReply : buildMessage:(AsyncReplyChannel<'Reply> -> 'Msg) * ?timeout:int -> 'Reply option
  ...

Full name: Microsoft.FSharp.Control.MailboxProcessor<_>

--------------------
new : body:(MailboxProcessor<'Msg> -> Async<unit>) * ?cancellationToken:System.Threading.CancellationToken -> MailboxProcessor<'Msg>

val async : AsyncBuilder

Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.async

val e : exn

member Event.Trigger : arg:'T -> unit

val x : HandlingMailbox<'T>

member HandlingMailbox.OnError : IEvent<exn>

Full name: Script.HandlingMailbox`1.OnError


 Triggered when an unhandled exception occurs

property Event.Publish: IEvent<exn>

member HandlingMailbox.Start : unit -> unit

Full name: Script.HandlingMailbox`1.Start


 Starts the mailbox processor

member MailboxProcessor.Start : unit -> unit

member HandlingMailbox.Receive : unit -> Async<'T>

Full name: Script.HandlingMailbox`1.Receive


 Receive a message from the mailbox processor

member MailboxProcessor.Receive : ?timeout:int -> Async<'Msg>

member HandlingMailbox.Post : v:'T -> unit

Full name: Script.HandlingMailbox`1.Post


 Post a message to the mailbox processor

val v : 'T

member MailboxProcessor.Post : message:'Msg -> unit

static member HandlingMailbox.Start : f:(HandlingMailbox<'a> -> Async<unit>) -> HandlingMailbox<'a>

Full name: Script.HandlingMailbox`1.Start


 Start the mailbox processor

val f : (HandlingMailbox<'a> -> Async<unit>)

val mbox : HandlingMailbox<'a>

member HandlingMailbox.Start : unit -> unit


 Starts the mailbox processor

val counter : HandlingMailbox<int>

Full name: Script.counter

val inbox : HandlingMailbox<int>

val printfn : format:Printf.TextWriterFormat<'T> -> 'T

Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.printfn

val data : int

member HandlingMailbox.Receive : unit -> Async<'T>


 Receive a message from the mailbox processor

val failwith : message:string -> 'T

Full name: Microsoft.FSharp.Core.Operators.failwith

property HandlingMailbox.OnError: IEvent<exn>


 Triggered when an unhandled exception occurs

member System.IObservable.Add : callback:('T -> unit) -> unit

member HandlingMailbox.Post : v:'T -> unit


 Post a message to the mailbox processor