> ... exhaustive pattern checking might well help out a lot of > people coming from untyped backgrounds...
Or even people from typed backgrounds. I worship at the altar of exhaustiveness checking.
Do you really want exhaustiveness, or is what you actually want safety? With -fwarn-incomplete-patterns: test1 = head [] test2 = x where (x:xs) = [] test3 = (\(x:xs) -> 1) [] test4 = f [] where f [] = 1 GHC reports that test4 has incomplete patterns, but the others don't. However, test4 is safe, but the others aren't. Exhaustiveness is a poor approximation of safety. GHC's exhaustiveness checker is a poor approximation of exhaustiveness. 2 is a poor approximation of pi :-) Using Catch, it reports that test1..3 were faulty, but test4 is safe. Thanks Neil