1 files changed, 2 insertions, 0 deletions
diff --git a/lib/top.ur b/lib/top.ur
index 91cab991..0bc345de 100644
--- a/lib/top.ur
+++ b/lib/top.ur
@@ -1,3 +1,5 @@
+fun not b = if b then False else True
+
 con idT (t :: Type) = t
 con record (t :: {Type}) = $t
 con fstTT (t :: (Type * Type)) = t.1