Update after executing <~

[pszot-concise]

let stream = Stream.once("foo").ownedBy(self)
println <~ stream
println <~ stream

I wonder if it's correct behaviour, that println will be called once. If I now did something like:

(label,"text") <~ stream

The label would never change.

[inamiy]

Yes, that's correct behavior.
Stream.once("foo") will send value once and complete immediately when first <~ is triggered because <~ works for both binding and firing.

There are several approaches to your desired behavior:

1. Use Stream.once("foo") |> delay(0) to delay firing until next run loop.

2. Create new stream for each println.

   let createStream: Void -> Stream<String> = { return Stream.once("foo").ownedBy(self) }
   println <~ createStream()
   println <~ createStream()

3. Use stream.progress(println) instead of <~.
   (Maybe, there should have some new binding only operator like below)

   let stream = Stream.once("foo").ownedBy(self)
   
   stream.progress(println)
   //println <~| stream   // `<~|` as binding only (not included in ver 0.12.x)
   
   println <~ stream    // `<~` as binding + fire