Wed, 21 Oct 2009 12:09:37 +0200 haftmann curried inter as canonical list operation (beware of argument order)
(0) -30000 -10000 -3000 -1000 -300 -100 -30 -10 -1 +1 +10 +30 +100 +300 +1000 +3000 +10000 +30000 tip