[Haskell-cafe] Intro to monad transformers

Henning Thielemann lemming at henning-thielemann.de
Sun Dec 26 20:34:35 CET 2010

On Sun, 26 Dec 2010, David Menendez wrote:

>       instance Show (MaybeT m a)
> This is never valid. You've defined show, shows, and showsPrec in terms of each other, creating
> unbounded recursion. Delete it.

Unfortunately, the -Wall option of GHC won't help here, since all the 
methods are defined by default methods.

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