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Sequence Generator from Async
Generates a sequence using a sequence generator and Async.StartWithContinuations. This is an attempt at modeling the OWIN delegate structure in F#
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|
module Seq =
let ofAsync (stream:System.IO.Stream) =
let count = 1024
let buffer = Array.zeroCreate count
let segment = ref (System.ArraySegment<_>())
let bytesRead = ref -1
let setSegment bytesRead = segment := System.ArraySegment<_>(buffer, 0, bytesRead)
let handleError e = printfn "%A" e
seq {
while !bytesRead <> 0 do
// Immediately processes the promise to create an ArraySegment containing the result.
Async.StartWithContinuations(stream.AsyncRead(buffer, 0, count), setSegment, handleError, handleError)
yield !segment
}
|
module Seq
from Microsoft.FSharp.Collections
val ofAsync : stream:System.IO.Stream -> seq<System.ArraySegment<byte>>
Full name: Script.Seq.ofAsync
val stream : System.IO.Stream
namespace System
namespace System.IO
type Stream =
inherit MarshalByRefObject
member BeginRead : buffer:byte[] * offset:int * count:int * callback:AsyncCallback * state:obj -> IAsyncResult
member BeginWrite : buffer:byte[] * offset:int * count:int * callback:AsyncCallback * state:obj -> IAsyncResult
member CanRead : bool
member CanSeek : bool
member CanTimeout : bool
member CanWrite : bool
member Close : unit -> unit
member CopyTo : destination:Stream -> unit + 1 overload
member Dispose : unit -> unit
member EndRead : asyncResult:IAsyncResult -> int
...
Full name: System.IO.Stream
val count : int
val buffer : byte []
module Array
from Microsoft.FSharp.Collections
val zeroCreate : count:int -> 'T []
Full name: Microsoft.FSharp.Collections.Array.zeroCreate
val segment : System.ArraySegment<byte> ref
Multiple items
val ref : value:'T -> 'T ref
Full name: Microsoft.FSharp.Core.Operators.ref
--------------------
type 'T ref = Ref<'T>
Full name: Microsoft.FSharp.Core.ref<_>
Multiple items
type ArraySegment<'T> =
struct
new : array:'T[] -> ArraySegment<'T> + 1 overload
member Array : 'T[]
member Count : int
member Equals : obj:obj -> bool + 1 overload
member GetHashCode : unit -> int
member Offset : int
end
Full name: System.ArraySegment<_>
--------------------
System.ArraySegment()
System.ArraySegment(array: 'T []) : unit
System.ArraySegment(array: 'T [], offset: int, count: int) : unit
val bytesRead : int ref
val setSegment : (int -> unit)
val bytesRead : int
val handleError : ('a -> unit)
val e : 'a
val printfn : format:Printf.TextWriterFormat<'T> -> 'T
Full name: Microsoft.FSharp.Core.ExtraTopLevelOperators.printfn
Multiple items
val seq : sequence:seq<'T> -> seq<'T>
Full name: Microsoft.FSharp.Core.Operators.seq
--------------------
type seq<'T> = System.Collections.Generic.IEnumerable<'T>
Full name: Microsoft.FSharp.Collections.seq<_>
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<_>
static member Async.StartWithContinuations : computation:Async<'T> * continuation:('T -> unit) * exceptionContinuation:(exn -> unit) * cancellationContinuation:(System.OperationCanceledException -> unit) * ?cancellationToken:System.Threading.CancellationToken -> unit
member System.IO.Stream.AsyncRead : count:int -> Async<byte []>
member System.IO.Stream.AsyncRead : buffer:byte [] * ?offset:int * ?count:int -> Async<int>
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