I want to believe the Anonymous Monk is the OP iang.
If so, what other errors are you getting?
Dave have pointed out that explicitly, that the package you used is Helper not HELPER.
Hope, your module is also saved as Helper.pm not HELPER.pm.
That been said, don't forget you only "exported" the foo subroutine.
However, if you still wanted the bar subroutine, then use Helper::bar() in your script.
Oouch!! Davido, got that answered before me !!! Why am i this slow typing..Ah...
Nice one, faster fingers.
If you tell me, I'll forget.
If you show me, I'll remember.
if you involve me, I'll understand.
--- Author unknown to me