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Asynchronous Timer

DoPeriodicWork schedules an async function periodically.

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module Async =
    open System.Threading
    open System.Threading.Tasks

    let AwaitTaskVoid : (Task -> Async<unit>) = Async.AwaitIAsyncResult >> Async.Ignore


    let DoPeriodicWork (f: unit -> Async<unit>) (interval: int) (token: CancellationToken) =
        async {
            while not token.IsCancellationRequested do
                do! f()
                do! Task.Delay(interval, token) |> AwaitTaskVoid
        }
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<_>
namespace System
namespace System.Threading
namespace System.Threading.Tasks
val AwaitTaskVoid : (Task -> Async<unit>)

Full name: Script.Async.AwaitTaskVoid
Multiple items
type Task =
  new : action:Action -> Task + 7 overloads
  member AsyncState : obj
  member ContinueWith : continuationAction:Action<Task> -> Task + 9 overloads
  member CreationOptions : TaskCreationOptions
  member Dispose : unit -> unit
  member Exception : AggregateException
  member Id : int
  member IsCanceled : bool
  member IsCompleted : bool
  member IsFaulted : bool
  ...

Full name: System.Threading.Tasks.Task

--------------------
type Task<'TResult> =
  inherit Task
  new : function:Func<'TResult> -> Task<'TResult> + 7 overloads
  member ContinueWith : continuationAction:Action<Task<'TResult>> -> Task + 9 overloads
  member Result : 'TResult with get, set
  static member Factory : TaskFactory<'TResult>

Full name: System.Threading.Tasks.Task<_>

--------------------
Task(action: System.Action) : unit
Task(action: System.Action, cancellationToken: CancellationToken) : unit
Task(action: System.Action, creationOptions: TaskCreationOptions) : unit
Task(action: System.Action<obj>, state: obj) : unit
Task(action: System.Action, cancellationToken: CancellationToken, creationOptions: TaskCreationOptions) : unit
Task(action: System.Action<obj>, state: obj, cancellationToken: CancellationToken) : unit
Task(action: System.Action<obj>, state: obj, creationOptions: TaskCreationOptions) : unit
Task(action: System.Action<obj>, state: obj, cancellationToken: CancellationToken, creationOptions: TaskCreationOptions) : unit

--------------------
Task(function: System.Func<'TResult>) : unit
Task(function: System.Func<'TResult>, cancellationToken: CancellationToken) : unit
Task(function: System.Func<'TResult>, creationOptions: TaskCreationOptions) : unit
Task(function: System.Func<obj,'TResult>, state: obj) : unit
Task(function: System.Func<'TResult>, cancellationToken: CancellationToken, creationOptions: TaskCreationOptions) : unit
Task(function: System.Func<obj,'TResult>, state: obj, cancellationToken: CancellationToken) : unit
Task(function: System.Func<obj,'TResult>, state: obj, creationOptions: TaskCreationOptions) : unit
Task(function: System.Func<obj,'TResult>, state: obj, cancellationToken: CancellationToken, creationOptions: TaskCreationOptions) : unit
type unit = Unit

Full name: Microsoft.FSharp.Core.unit
static member Async.AwaitIAsyncResult : iar:System.IAsyncResult * ?millisecondsTimeout:int -> Async<bool>
static member Async.Ignore : computation:Async<'T> -> Async<unit>
val DoPeriodicWork : f:(unit -> Async<unit>) -> interval:int -> token:CancellationToken -> Async<unit>

Full name: Script.Async.DoPeriodicWork
val f : (unit -> Async<unit>)
val interval : int
Multiple items
val int : value:'T -> int (requires member op_Explicit)

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

--------------------
type int = int32

Full name: Microsoft.FSharp.Core.int

--------------------
type int<'Measure> = int

Full name: Microsoft.FSharp.Core.int<_>
val token : CancellationToken
Multiple items
type CancellationToken =
  struct
    new : canceled:bool -> CancellationToken
    member CanBeCanceled : bool
    member Equals : other:CancellationToken -> bool + 1 overload
    member GetHashCode : unit -> int
    member IsCancellationRequested : bool
    member Register : callback:Action -> CancellationTokenRegistration + 3 overloads
    member ThrowIfCancellationRequested : unit -> unit
    member WaitHandle : WaitHandle
    static member None : CancellationToken
  end

Full name: System.Threading.CancellationToken

--------------------
CancellationToken()
CancellationToken(canceled: bool) : unit
val async : AsyncBuilder

Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.async
val not : value:bool -> bool

Full name: Microsoft.FSharp.Core.Operators.not
property CancellationToken.IsCancellationRequested: bool

More information

Link:http://fssnip.net/qt
Posted:10 years ago
Author:
Tags: async , timer