Method Scan

Scan<TSource>(IAsyncEnumerable<TSource>, Func<TSource, TSource, TSource>)

Performs a scan (inclusive prefix sum) on a sequence of elements. This operator is similar to Aggregate<TSource>(IEnumerable<TSource>, Func<TSource, TSource, TSource>) except that Scan<TSource>(IAsyncEnumerable<TSource>, Func<TSource, TSource, TSource>) returns the sequence of intermediate results as well as the final one.

Declaration

public static IAsyncEnumerable<TSource> Scan<TSource>(this IAsyncEnumerable<TSource> source, Func<TSource, TSource, TSource> transformation)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	Source sequence
Func<TSource, TSource, TSource>	transformation	Transformation operation

Returns

Type	Description
IAsyncEnumerable<TSource>	The scanned sequence

Type Parameters

Name	Description
TSource	Type of elements in source sequence

Remarks

This operator uses deferred execution and streams its result.

Exceptions

Type	Condition
ArgumentNullException	source or transformation is null.

Scan<TSource, TState>(IAsyncEnumerable<TSource>, TState, Func<TState, TSource, TState>)

Performs a scan (inclusive prefix sum) on a sequence of elements. This operator is similar to Aggregate<TSource, TAccumulate>(IEnumerable<TSource>, TAccumulate, Func<TAccumulate, TSource, TAccumulate>) except that Scan<TSource, TState>(IAsyncEnumerable<TSource>, TState, Func<TState, TSource, TState>) returns the sequence of intermediate results as well as the final one.

Declaration

public static IAsyncEnumerable<TState> Scan<TSource, TState>(this IAsyncEnumerable<TSource> source, TState seed, Func<TState, TSource, TState> transformation)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	Source sequence
TState	seed	Initial state to seed
Func<TState, TSource, TState>	transformation	Transformation operation

Returns

Type	Description
IAsyncEnumerable<TState>	The scanned sequence

Type Parameters

Name	Description
TSource	Type of elements in source sequence
TState	Type of state

Remarks

This operator uses deferred execution and streams its result.

Exceptions

Type	Condition
ArgumentNullException	source or transformation is null.