Re: [Haskell-beginners] finding the cause of an error (here head: empty list)

On Mon, Apr 1, 2013 at 12:17 AM, David McBride wrote:

People tend to use pattern matching on lists or case statements on the list.

Yes, and activate -Wall to detect places where the pattern matching isn't covering all cases. Modulo the actual exception, head is equivalent to head (x:xs) = x Notice the absence of a "head []" definition. -- Kim-Ee