checkPrecMatch
*Research> :r
Compiling Statistics.DescriptiveAnalysis.KeyHistoryListImpl ( ./Statistics/DescriptiveAnalysis/KeyHistoryListImpl.hs, interpreted )
: panic! (the `impossible' happened, GHC version 6.4.2):
checkPrecMatch
Please report this as a compiler bug. See:
http://www.haskell.org/ghc/reportabug
This happened when i compile in GHCI:
module Test where
class TestInfo a where
type Bla = String
-- GADT Descriptors
data Descriptor where
BA :: String -> Descriptor
GA :: (Show a, TestInfo a) => Either a (String, String) -> Descriptor
SA :: String -> Descriptor
AA :: String -> [Bla]-> Descriptor
TA :: Bla -> Bla -> Bla -> Descriptor
instance Eq Descriptor where
(BA descr1) == (BA descr2) = descr1 == descr2
(GA grpsubj) == (GA grpsubj2) = show grpsubj == show grpsubj2 -- might not be correct
(SA descr) == (SA descr2) = descr == descr2
(AA descr keys) == (AA descr2 keys2) = (descr == descr2) && (keys == keys2)
(TA orikey key1 key2) == (TA orikeyB key1B key2B) = (orikey == orikeyB) && (key1 == key1B) && (key2 == key2B)
(==) = error "Error pattern not found in (==)"
The last line give the compilation error
Peter, peteanom@gmail.com