Re: Pattern match failure leads to lots of output
"Neil Mitchell" <[email protected]> Fri, 1 Sep 2006 17:41:44 +0100
| Newsgroups | gmane.comp.lang.haskell.hugs.user |
|---|---|
| Message-ID | <[email protected]> |
Hi > It would probably be better to hide the dictionary arguments and the _vNNN > suffixes altogether in pattern match errors. Can you put a boiled-down > example in the BTS? Here is a small failing example, with context and stuff its hard to know when I get it minimal: > data Maybe1 a = Just1 a | Nothing1 deriving Eq > data Maybe2 a = Just2 (Maybe1 a) | Nothing2 deriving Eq > crash_me = g (Just2 (Just1 1)) > g x = f Nothing2 > where f y | x == y && False = undefined Run crash_me to see a lot of output. Ross: I can't test the code you sent me right now, since I'm on a machine without a C compiler, but should be back by Wednesday. Thanks Neil