Ah, that's a really good point. It seems then that there is a use for implicitly unwrapped newtypes, but perhaps only when you never really wanted to use a newtype to begin with but had to in order to use a different instance declaration for the same type. That suggests that the feature we'd really like is a way to declare that we want a type in a context to act as if it had a different instance declaration for a given typeclass, without having to go through newtype.
Cheers, Greg On Dec 2, 2009, at 5:08 PM, Greg Fitzgerald wrote: > Gregory Crosswhite <[email protected]> wrote: >> Out of curiosity, why would one want a "newtype" that were unwrapped >> implicitly, rather than just using "type"? > > One reason might be because you only switched from 'type' to 'newtype' > so that you could write more refined Arbitrary instances for your > QuickCheck tests. > > -Greg _______________________________________________ Haskell-Cafe mailing list [email protected] http://www.haskell.org/mailman/listinfo/haskell-cafe
