Move stuff around + add lean and idris experiments

purescript/streams/src/Main.purs

@@ -0,0 +1,38 @@
+module Main where
+
+import Prelude
+
+import Data.Tuple (Tuple(..))
+import Effect (Effect)
+import Effect.Class (class MonadEffect)
+import Effect.Class.Console (logShow)
+import Pipes (await, for, yield, (>->))
+import Pipes.Core (Consumer_, Producer_, runEffect)
+import Pipes.Prelude (take)
+import Pipes.Prelude as Pipes
+
+naturals :: forall m. Monad m => Producer_ Int m Unit
+naturals = go 0
+  where
+  go n = do
+    yield n
+    go (n + 1)
+
+logAll :: forall a m. MonadEffect m => Show a => Consumer_ a m Unit
+logAll = do
+  showable <- await
+  logShow showable
+  logAll
+
+nNaturals :: forall m. Monad m => Int -> Producer_ Int m Unit
+nNaturals n = naturals >-> take n
+
+merger :: forall m. Monad m => Producer_ (Tuple Int Int) m Unit
+merger = 
+  for (nNaturals 3) \a ->
+    for (nNaturals 3 >-> Pipes.map ((+) 4)) \b ->
+      yield $ Tuple a b
+
+
+main :: Effect Unit
+main = runEffect ((nNaturals 3 <> nNaturals 3) >-> logAll)