Understanding FRP Loops and Forward referencing

[torgeadelin]

Hi! I'm new to the sodium library and I have a question regarding forward referencing and Stream/Cell Loops.
From what I understood from the book, the purpose of these loops are to facilitate the creation of circular dependencies between streams/cells. I looked at the example in the book with the spinner. It totally makes sense and I understand why this is needed in Java(since it's not a functional programming language).

On the other hand, for the implementation in scala, can't we just us lazy values for the forward referencing?

Thanks,
Catalin

[clinuxrulz]

Provided the implementation in scala is lazy. Then I'd say, yes you can. I'm not familiar with the current scala implementation, but new nodes are not required in the graph to do the forward reference. Reactive Banana used fixed point combinators for its forward references.

[the-real-blackh]

To use laziness to represent loops directly is very tricky. I don't think it would work in Scala. As far as I know, Haskell is the only language that's capable of it.