libghc-classy-prelude-dev 0.5.4-2build3 (amd64 binary) in ubuntu trusty

 Focuses on using common typeclasses when possible, and creating new ones
 to avoid name clashing. Exposes many recommended datastructures (Map,
 ByteString, etc) directly without requiring long import lists and
 qualified modules.
 .
 This package provides a library for the Haskell programming language.
 See http://www.haskell.org/ for more information on Haskell.