A Callbag operator that will emit the current
Index
of an item along with the emitted item. And it returns a pullable / listenable source, depends on the given callbag sources types.
Examples
_ = from(1...5)
|> indices()
|> forEach(print) // (0, 1)
// (1, 2)
// (2, 3)
// (3, 4)
// (4, 5)