Helper to create SourceTOut, TMat from IPublisher. Construct a transformation starting with given publisher. The transformation steps are executed by a series of IProcessor instances that mediate the flow of elements downstream and the propagation of back-pressure upstream.

public static Source<T, NotUsed> FromPublisher<T>(
	IPublisher<T> publisher
)

static member FromPublisher : 
        publisher : IPublisher<'T> -> Source<'T, NotUsed>