See http://ghc.haskell.org/trac/ghc/wiki/DefaultSuperclassInstances
| -Original Message-
| From: Haskell-Cafe [mailto:haskell-cafe-boun...@haskell.org] On Behalf
| Of Henning Thielemann
| Sent: 26 August 2013 20:07
| To: Frantisek Farka
| Cc: Haskell Cafe
| Subject: Re: [Haskell-cafe
The problem of refinement of type classes annoys me from time to time
when I work on the NumericPrelude. It is an experimental type class
hierarchy for mathematical types. Sometimes a new data type T shall be
implemented and it turns out that you can implement only a part of all
methods of
