AsyncEnumerableExtensions.Peek<T> Method
Definition
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Peeks at the first element of an async enumerable sequence without consuming the sequence.
public static System.Threading.Tasks.ValueTask<(bool HasValue, T First, System.Collections.Generic.IAsyncEnumerable<T> Source)> Peek<T>(this System.Collections.Generic.IAsyncEnumerable<T> source, System.Threading.CancellationToken cancellationToken = default);static member Peek : System.Collections.Generic.IAsyncEnumerable<'T> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<ValueTuple<bool, 'T, System.Collections.Generic.IAsyncEnumerable<'T>>><Extension()>
Public Function Peek(Of T) (source As IAsyncEnumerable(Of T), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of ValueTuple(Of Boolean, T, IAsyncEnumerable(Of T)))Type Parameters
- T
The type of elements in the sequence.
Parameters
- source
- IAsyncEnumerable<T>
The source async enumerable sequence.
- cancellationToken
- CancellationToken
A cancellation token to observe while peeking at the sequence.
Returns
A tuple containing a flag indicating if the sequence has a value, the first element, and the complete sequence including the peeked element.
