28 Feb
2012
28 Feb
'12
8:58 p.m.
Except when l == [], but the second equation can be replaced by this nicer one.
Even then. :) (zipWith f l (tail l)) first tries to match l with pattern (a:as), and if that fails it will not touch its other argument (tail l).
Hm, you're right, it did work for empty lists. I wonder if one dare trust it to always be so. /Johan