MoreEnumerableLeadTSource, TResult(IEnumerableTSource, Int32, FuncTSource, TSource, TResult) Method

Produces a projection of a sequence by evaluating pairs of elements separated by a positive offset.

Definition

Namespace: MoreLinq
Assembly: MoreLinq (in MoreLinq.dll) Version: 4.0.0+092a40d82a1b280568ffa006d9a210bdec0792cd

C#

public static IEnumerable<TResult> Lead<TSource, TResult>(
	this IEnumerable<TSource> source,
	int offset,
	Func<TSource, TSource, TResult> resultSelector
)

VB

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

C++

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

F#

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

Parameters

source IEnumerableTSource: The sequence over which to evaluate lead.
offset Int32: The offset (expressed as a positive number) by which to lead each element of the sequence.
resultSelector FuncTSource, TSource, TResult: A projection function which accepts the current and subsequent (lead) element (in that order) and produces a result.

Type Parameters

TSource: The type of the elements in the source sequence.
TResult: The type of the elements in the result sequence.

Return Value

IEnumerableTResult
A sequence produced by projecting each element of the sequence with its lead pairing.

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 evaluates in a deferred and streaming manner.

For elements of the sequence that are less than offset items from the end, default(T) is used as the lead value.