#1588: unrequested generalized newtype deriving?
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Reporter: SamB | Owner:
Type: bug | Status: new
Priority: normal | Milestone:
Component: Compiler | Version: 6.6
Severity: normal | Keywords:
Difficulty: Unknown | Os: Unknown
Testcase: | Architecture: Unknown
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Consider the two type definitions:
{{{
newtype MaybeT m a = MaybeT { runMaybeT :: m (Maybe a) } deriving Eq
data MaybeT' m a = MaybeT' { runMaybeT' :: m (Maybe a) } deriving Eq
}}}
Why is it that the former compiles, with no flags of any kind, but the
latter does not? It seems like generalized newtype deriving is happening
when unrequested and undesired...
(I'm trying to figure out how Derive should derive Eq, and compiler bugs
don't help much ;-)
--
Ticket URL: <http://hackage.haskell.org/trac/ghc/ticket/1588>
GHC <http://www.haskell.org/ghc/>
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