1 files changed, 7 insertions, 0 deletions
diff --git a/lib/ur/monad.ur b/lib/ur/monad.ur
new file mode 100644
index 00000000..41f44d3a
--- /dev/null
+++ b/lib/ur/monad.ur
@@ -0,0 +1,7 @@
+fun exec [m ::: Type -> Type] (_ : monad m) [ts ::: {Type}] r (fd : folder ts) =
+    foldR [m] [fn ts => m $ts]
+    (fn [nm :: Name] [v :: Type] [rest :: {Type}] [[nm] ~ rest] action acc =>
+        this <- action;
+        others <- acc;
+        return ({nm = this} ++ others))
+    (return {}) [ts] fd r