Make the Timeout exception a newtype instead of a datatype

diff --git a/System/Timeout.hs b/System/Timeout.hs
index b1c79b3..dbd7181 100644 (file)
--- a/System/Timeout.hs
+++ b/System/Timeout.hs
@@ -34,7 +34,7 @@ import Data.Unique         (Unique, newUnique)
 -- interrupt the running IO computation when the timeout has
 -- expired.
 
-data Timeout = Timeout Unique deriving Eq
+newtype Timeout = Timeout Unique deriving Eq
 INSTANCE_TYPEABLE0(Timeout,timeoutTc,"Timeout")
 
 instance Show Timeout where