Re: New extension in GHC: newtype deriving clause

John Hughes wrote:

Simon PJ and I have come up with an extension to newtype deriving clauses which is intended to make it easier to make types abstract.

The new extension allows you to derive these instances, just by adding the classes to the deriving clause of the newtype declaration.

I like this, and I suggested it about 10 years ago. :-) (And we have it in BlueSpec.) -- Lennart