1 files changed, 11 insertions, 0 deletions
diff --git a/lib/ur/listPair.ur b/lib/ur/listPair.ur
index a46cf187..8d1c873e 100644
--- a/lib/ur/listPair.ur
+++ b/lib/ur/listPair.ur
@@ -8,3 +8,14 @@ fun mapX [a] [b] [ctx ::: {Unit}] f =
     in
         mapX'
     end
+
+fun all [a] [b] f =
+    let
+        fun all' ls1 ls2 =
+            case (ls1, ls2) of
+                ([], []) => True
+              | (x1 :: ls1, x2 :: ls2) => f x1 x2 && all' ls1 ls2
+              | _ => False
+    in
+        all'
+    end