[Haskell-cafe] Implicit Multi Threading in Switch Case

[Yotam Ohad]

Hi,
After reading "Push-Pull Functional Reactive Programming
<https://pdfs.semanticscholar.org/fb7a/879d639641341e025197b40afad9e21f0ce5.pdf>"
I had an idea about deciding which, of two events, comes first. Instead of
using forkIO, I tried something like the following:

infi :: Maybe Int
infi = infi

stop :: Maybe Int
stop = Nothing

test :: Int
test = case (infi, stop) of
    (Nothing, Just _) -> 1
    (_, _) -> 2

Here, infi is an action that never ends, and stop a function that ends
immediately. I thought that the compiler would see that stop evaluates
immediately to Nothing and thus will return 2, but it tries to evaluate
infi and get stuck.

I think it happens because I am using a tuple to hold both values (but not
really sure about it). Do you know a way to make this arrangement work?

Yotam
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