diff --git a/src/Handler/Course/ParticipantInvite.hs b/src/Handler/Course/ParticipantInvite.hs
index 14cd08930..82ebe492f 100644
--- a/src/Handler/Course/ParticipantInvite.hs
+++ b/src/Handler/Course/ParticipantInvite.hs
@@ -56,7 +56,7 @@ tutorialDefaultName (Just ttyp) =
 
 formatDayForTutName :: Day -> CI Text -- "%yy_%mm_%dd" -- Do not use user date display setting, since tutorial default names must be universal regardless of user
 -- formatDayForTutName = CI.mk . formatTime' "%y_%m_%d" -- we don't want to go monadic for this
-formatDayForTutName d = CI.mk . Text.map d2u . Text.drop 2 . tshow 
+formatDayForTutName = CI.mk . Text.map d2u . Text.drop 2 . tshow 
   where 
     d2u '-' = '_'
     d2u  c  =  c