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Observable.filter<'T> Function (F#)

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

Returns an observable which filters the observations of the source by the given function. The observable will see only those observations for which the predicate returns true. The predicate is executed once for each subscribed observer. The returned object also propagates error observations 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.filter : ('T -> bool) -> IObservable<'T> -> IObservable<'T>

// Usage:
Observable.filter predicate source


predicate Type: 'T ->bool

The function to apply to observations to determine if it should be kept.

source Type: IObservable<'T>

The input Observable.

Return Value

An Observable that filters observations based on filter.


This function is named Filter 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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