libghc-rank2classes-dev 1.3.2.1-2 (amd64 binary) in ubuntu groovy

 A mirror image of the standard type constructor class hierarchy
 rooted in 'Functor', except with methods of rank 2 types and class
 instances of kind (k -> *) -> *. The classes enable generic handling
 of heterogenously typed data structures and other neat tricks.
 .
 This package provides a library for the Haskell programming language.
 See http://www.haskell.org/ for more information on Haskell.