PairwiseExtensionPairwiseTSource, TResult Method

Returns a sequence resulting from applying a function to each element in the source sequence and its predecessor, with the exception of the first element which is only returned as the predecessor of the second element.

Namespace: MoreLinq.Extensions
Assembly: MoreLinq (in MoreLinq.dll) Version: 3.0.0

Syntax

C++

Copy

public static IEnumerable<TResult> Pairwise<TSource, TResult>(
	this IEnumerable<TSource> source,
	Func<TSource, TSource, TResult> resultSelector
)

<ExtensionAttribute>
Public Shared Function Pairwise(Of TSource, TResult) ( 
	source As IEnumerable(Of TSource),
	resultSelector As Func(Of TSource, TSource, TResult)
) As IEnumerable(Of TResult)

public:
[ExtensionAttribute]
generic<typename TSource, typename TResult>
static IEnumerable<TResult>^ Pairwise(
	IEnumerable<TSource>^ source, 
	Func<TSource, TSource, TResult>^ resultSelector
)

[<ExtensionAttribute>]
static member Pairwise : 
        source : IEnumerable<'TSource> * 
        resultSelector : Func<'TSource, 'TSource, 'TResult> -> IEnumerable<'TResult>

Parameters

source: Type: System.Collections.GenericIEnumerableTSource
The source sequence.
resultSelector: Type: SystemFuncTSource, TSource, TResult
A transform function to apply to each pair of sequence.

Type Parameters

TSource: The type of the elements of source.
TResult: The type of the element of the returned sequence.

Return Value

Type: IEnumerableTResult
Returns the resulting sequence.

Usage Note

In Visual Basic and C#, you can call this method as an instance method on any object of type IEnumerableTSource. When you use instance method syntax to call this method, omit the first parameter. For more information, see Extension Methods (Visual Basic) or Extension Methods (C# Programming Guide).

Remarks

This operator uses deferred execution and streams its results.

Examples

Copy

int[] numbers = { 123, 456, 789 };
var result = numbers.Pairwise((a, b) => a + b);

The result variable, when iterated over, will yield 579 and 1245, in turn.

Reference

PairwiseExtension Class