# HG changeset patch
# User Adam Chlipala <adam@chlipala.net>
# Date 1287516372 14400
# Node ID 0bf73c3e4563e986954dae523ba596399c2e6ec2
# Parent  726f0caeea3fab44cf826fca5d4a5e3e8329bb19
Monad.appR3

diff -r 726f0caeea3f -r 0bf73c3e4563 lib/ur/monad.ur
--- a/lib/ur/monad.ur	Tue Oct 19 11:51:53 2010 -0400
+++ b/lib/ur/monad.ur	Tue Oct 19 15:26:12 2010 -0400
@@ -112,3 +112,13 @@
          f [nm] [t] r1.nm r2.nm)
      (fn _ _ => return ())
      fl
+
+fun appR3 [K] [m] (_ : monad m) [tf1 :: K -> Type] [tf2 :: K -> Type] [tf3 :: K -> Type]
+           (f : nm :: Name -> t :: K -> tf1 t -> tf2 t -> tf3 t -> m unit)
+           [r ::: {K}] (fl : folder r) =
+    @Top.fold [fn r :: {K} => $(map tf1 r) -> $(map tf2 r) -> $(map tf3 r) -> m unit]
+     (fn [nm :: Name] [t :: K] [rest :: {K}] [[nm] ~ rest] acc r1 r2 r3 =>
+         acc (r1 -- nm) (r2 -- nm) (r3 -- nm);
+         f [nm] [t] r1.nm r2.nm r3.nm)
+     (fn _ _ _ => return ())
+     fl
diff -r 726f0caeea3f -r 0bf73c3e4563 lib/ur/monad.urs
--- a/lib/ur/monad.urs	Tue Oct 19 11:51:53 2010 -0400
+++ b/lib/ur/monad.urs	Tue Oct 19 15:26:12 2010 -0400
@@ -70,3 +70,8 @@
              -> tf1 :: (K -> Type) -> tf2 :: (K -> Type)
              -> (nm :: Name -> t :: K -> tf1 t -> tf2 t -> m unit)
              -> r ::: {K} -> folder r -> $(map tf1 r) -> $(map tf2 r) -> m unit
+
+val appR3 : K --> m ::: (Type -> Type) -> monad m
+             -> tf1 :: (K -> Type) -> tf2 :: (K -> Type) -> tf3 :: (K -> Type)
+             -> (nm :: Name -> t :: K -> tf1 t -> tf2 t -> tf3 t -> m unit)
+             -> r ::: {K} -> folder r -> $(map tf1 r) -> $(map tf2 r) -> $(map tf3 r) -> m unit