[Haskell-cafe] case switch covering all possible constructor but still fails

Daniel Trstenjak daniel.trstenjak at gmail.com
Sat Apr 13 12:08:31 CEST 2013

Hi Nathan,

> DataAlt c | Right tag <- genDataConTag c -> return $ Cond tag

Are you sure, that genDataConTag always returns a 'Right'?
If it returns a 'Left', than the pattern won't match.


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