[Haskell-cafe] Implicit newtype unwrapping

Luke Palmer lrpalmer at gmail.com
Wed Dec 2 20:22:07 EST 2009

On Wed, Dec 2, 2009 at 6:08 PM, Greg Fitzgerald <garious at gmail.com> wrote:
> Gregory Crosswhite <gcross at phys.washington.edu> 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.

Maybe that is an indication that we should use a checker combinator
library instead of typeclasses for automated testing.  Less
convenient, more adaptable.


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