Folding through a functor

1 files changed, 26 insertions, 0 deletions

diff --git a/tests/foldm.lac b/tests/foldm.lac
new file mode 100644
index 00000000..64d30ba2
--- /dev/null
+++ b/tests/foldm.lac
@@ -0,0 +1,26 @@
+con currier = fold (fn nm => fn t => fn acc => t -> acc) {}
+
+signature S = sig
+        type t
+        val x : t
+
+        con rs :: {Type}
+        val create : currier rs -> t
+end
+
+functor Currier (M : sig con rs :: {Type} end) : S where con rs = M.rs = struct
+        val currier : rs :: {Type} -> currier rs =
+                fold [currier] (fn nm :: Name => fn t :: Type => fn rest :: {Type} => fn acc => fn x : t => acc) {}
+
+        type t = currier M.rs
+        val x = currier [M.rs]
+
+        con rs = M.rs
+        val create : t -> t = fn x => x
+end
+
+structure ChefsSpecial = Currier(struct
+        con rs = [A = int, B = float]
+end)
+
+val main = ChefsSpecial.x