Move stuff around + add lean and idris experiments

purescript/compose/src/Main.purs

@@ -0,0 +1,44 @@
+module Main where
+
+import Prelude
+
+import Compose as Compose
+import Data.Exists (Exists)
+import Effect (Effect)
+import Effect.Class.Console (logShow)
+import Unsafe.Coerce (unsafeCoerce)
+
+
+c :: Int -> Int
+c = Compose.do
+    add2
+    double
+
+add2 :: Int -> Int
+add2 = (+) 2
+
+double :: Int -> Int
+double = (*) 2
+
+newtype I a = I a
+type EI = Exists I
+
+type Showable f = forall result. (forall r. Show r => f r -> result) -> result
+
+mkShowable :: forall a f. Show a => f a -> Showable f
+mkShowable a f = f a
+
+test :: String
+test = do
+  I something <- mkShowable $ I 0
+  show something
+  where
+  bind :: forall f result. Showable f -> (forall r. Show r => f r -> result) -> result 
+  bind e f = e f
+
+  magicShow :: forall r. r -> String
+  magicShow = unsafeCoerce
+
+main :: Effect Unit
+main = do
+  logShow $ c 3