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AsyncBuilder.TryWith<'T> Method (F#)

Den Delimarsky|Last Updated: 8/18/2017
1 Contributor

Implements try...with in asynchronous computations.

Namespace/Module Path: Microsoft.FSharp.Control

Assembly: FSharp.Core (in FSharp.Core.dll)


// Signature:
member this.TryWith : Async<'T> * (exn -> Async<'T>) -> Async<'T>

// Usage:
asyncBuilder.TryWith (computation, catchHandler)


computation Type: Async<'T>

The input computation.

catchHandler Type: exn->Async<'T>

The function to run when computation throws an exception.

Return Value

An asynchronous computation that executes computation and calls catchHandler if an exception is thrown.


This function creates an asynchronous computation that runs computation and returns its result. If an exception happens then catchHandler(exn) is called and the resulting computation executed instead.

A cancellation check is performed when the computation is executed. The existence of this method permits the use of try...with in the async { ... } computation expression syntax.


Windows 8, Windows 7, Windows Server 2012, Windows Server 2008 R2

Version Information

F# Core Library Versions

Supported in: 2.0, 4.0, Portable

See Also

Control.AsyncBuilder Class (F#)

Microsoft.FSharp.Control Namespace (F#)

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