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Observable.choose<'T,'U> Function (F#)

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

Returns an observable which chooses a projection of observations from the source using the given function. The returned object will trigger observations for which the splitter returns a Some value. The returned object also propagates all errors arising from the source and completes when the source completes.

Namespace/Module Path: Microsoft.FSharp.Control.Observable

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


// Signature:
Observable.choose : ('T -> 'U option) -> IObservable<'T> -> IObservable<'U>

// Usage:
Observable.choose chooser source


chooser Type: 'T -> 'Uoption

The function that returns Some for observations to be propagated and None for observations to ignore.

source Type: IObservable<'T>

The input Observable.

Return Value

An Observable that only propagates some of the observations from the source.


This function is named Choose in compiled assemblies. If you are accessing the function from a language other than F#, or through reflection, use this name.


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.Observable Module (F#)

Microsoft.FSharp.Control Namespace (F#)

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