feat(third_party/bazel): Check in rules_haskell from Tweag

third_party/bazel/rules_haskell/tutorial/lib/Bool.hs

@@ -0,0 +1,19 @@
+-- base is not available when no dependencies, so we have to define everything
+-- from scratch.
+{-# LANGUAGE NoImplicitPrelude #-}
+
+module Bool where
+
+data Bool = False | True
+
+not :: Bool -> Bool
+not False = True
+not True = False
+
+and :: Bool -> Bool -> Bool
+and True True = True
+and _ _ = False
+
+or :: Bool -> Bool -> Bool
+or False False = False
+or _ _ = True