Source.Unfold(TState, TElem) Method

SourceUnfoldTState, TElem Method

Create a SourceTOut, TMat that will unfold a value of type TState into a pair of the next state TState and output elements of type TElem.

Namespace: Akka.Streams.Dsl
Assembly: Akka.Streams (in Akka.Streams.dll) Version: 1.2.3.42 (1.2.3.42)

Syntax

public static Source<TElem, NotUsed> Unfold<TState, TElem>(
	TState state,
	Func<TState, Tuple<TState, TElem>> unfold
)

static member Unfold : 
        state : 'TState * 
        unfold : Func<'TState, Tuple<'TState, 'TElem>> -> Source<'TElem, NotUsed>

Type: SourceTElem, NotUsed
TBD

Examples

For example, all the Fibonacci numbers under 10M:

Source.unfold(0 → 1) {
 case (a, _) if a > 10000000 ⇒ None
 case (a, b) ⇒ Some((b → (a + b)) → a)
}