As-is, no. As Michael said, that would defeat the purpose of a newtype. However, there is a generic way: all newtypes are given instances of Coercible, so instead of individual unwrap functions you can use coerce from Data.Coerce.


On Aug 7, 2016 7:59 AM, "Imants Cekusins" <imantc@gmail.com> wrote:
> newtype B = B { toBool :: Bool }

yep, this works well. toBool b1 is easy enough ;)

I wondered if there was an easy (with deriving etc) way to test B as it is. If there isn't - no biggie.



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