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Visual Studio 2012
Visual F#
F# Core Library Reference
Microsoft.FSharp.Collections Namespace
List Module
List.append<'T> Function
List.average<^T> Function
List.averageBy<'T,^U> Function
List.choose<'T,'U> Function
List.collect<'T,'U> Function
List.concat<'T> Function
List.empty<'T> Type Function
List.exists<'T> Function
List.exists2<'T1,'T2> Function
List.filter<'T> Function
List.find<'T> Function
List.findIndex<'T> Function
List.fold<'T,'State> Function
List.fold2<'T1,'T2,'State> Function
List.foldBack<'T,'State> Function
List.foldBack2<'T1,'T2,'State> Function
List.forall<'T> Function
List.forall2<'T1,'T2> Function
List.head<'T> Function
List.init<'T> Function
List.isEmpty<'T> Function
List.iter<'T> Function
List.iter2<'T1,'T2> Function
List.iteri<'T> Function
List.iteri2<'T1,'T2> Function
List.length<'T> Function
List.map<'T,'U> Function
List.map2<'T1,'T2,'U> Function
List.map3<'T1,'T2,'T3,'U> Function
List.mapi<'T,'U> Function
List.mapi2<'T1,'T2,'U> Function
List.max<'T> Function
List.maxBy<'T,'U> Function
List.min<'T> Function
List.minBy<'T,'U> Function
List.nth<'T> Function
List.ofArray<'T> Function
List.ofSeq<'T> Function
List.partition<'T> Function
List.permute<'T> Function
List.pick<'T,'U> Function
List.reduce<'T> Function
List.reduceBack<'T> Function
List.replicate<'T> Function
List.rev<'T> Function
List.scan<'T,'State> Function
List.scanBack<'T,'State> Function
List.sort<'T> Function
List.sortBy<'T,'Key> Function
List.sortWith<'T> Function
List.sum<^T> Function
List.sumBy<'T,^U> Function
List.tail<'T> Function
List.toArray<'T> Function
List.toSeq<'T> Function
List.tryFind<'T> Function
List.tryFindIndex<'T> Function
List.tryPick<'T,'U> Function
List.unzip<'T1,'T2> Function
List.unzip3<'T1,'T2,'T3> Function
List.zip<'T1,'T2> Function
List.zip3<'T1,'T2,'T3> Function
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List.partition<'T> Function (F#)

Visual Studio 2012

Splits the collection into two collections, containing the elements for which the given predicate returns true and false respectively.

Namespace/Module Path: Microsoft.FSharp.Collections.List

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

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// Signature:
List.partition : ('T -> bool) -> 'T list -> 'T list * 'T list

// Usage:
List.partition predicate list
predicate

Type: 'T -> bool

The function to test the input elements.

list

Type: 'T list

The input list.

A list containing the elements for which the predicate evaluated to false and a list containing the elements for which the predicate evaluated to true.

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

The following code example shows how to use List.partition.

F#
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let list1 = [ 1 .. 10 ]
let listEven, listOdd = List.partition (fun elem -> elem % 2 = 0) list1
printfn "Evens: %A\nOdds: %A" listEven listOdd

Output 

Evens: [2; 4; 6; 8; 10]
Odds: [1; 3; 5; 7; 9]

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

F# Core Library Versions

Supported in: 2.0, 4.0, Portable

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