On Sun, Aug 28, 2011 at 18:44, Philip Holzenspies <p...@st-andrews.ac.uk>wrote:
> instance (Typeable1 m, Monad m) => Typeable (MyADT m) where > typeOf t@(MyADT _) > typeOf is usually invoked with an undefined parameter; it should use types, never values. Here you've defined it to deconstruct what it's passed, which means that anything that uses it in the usual way (`typeOf (undefined :: someType)') will immediately throw undefined. You don't need a deconstructor there; you (correctly) throw away the value, and it doesn't provide any type information not already available from the instance declaration. `typeOf t' should be good enough. -- brandon s allbery allber...@gmail.com wandering unix systems administrator (available) (412) 475-9364 vm/sms
_______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe