... 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.
Anyone know why it isn't the default?
I have been bleating to GHC Central about the generally low level of the default warnings. I even accused them of being tarred with the same brush as Richard Stallman! Their (reasonable) response was that they would rather wait for the user community to reach a consensus on exactly *which* warnings should be on by default. I myself like to compile with -Wall -fno-warn-name-shadowing, but I recognize that these are questions about which reasonable people could differ. I think if we could reach a consensus on the list, we might see a stronger level of warnings in 6.12. Norman P.S. The exhaustiveness checker does need improvement, and it is completely unaware of GADT's. My code is littered with pattern matches where the last case is foo _ = can't match where can't_match :: a can't_match = panic "the GADT pattern matcher is too stupid to live" I would really like to get rid of these. I hate wildcard matches, but I can't put in the constructors because they don't typecheck. And if I put in nothing, the exhaustiveness checker bleats. And I typically compile with -Werror.