diff --git a/src/Data/String.purs b/src/Data/String.purs
index b7d8213..4a56cb2 100644
--- a/src/Data/String.purs
+++ b/src/Data/String.purs
@@ -72,7 +72,7 @@ foreign import _toChar :: (forall a. a -> Maybe a)
 
 -- | Returns `true` if the given string is empty.
 null :: String -> Boolean
-null s = length s == zero
+null s = s == ""
 
 -- | Returns the first character and the rest of the string,
 -- | if the string is not empty.