{cabal}: cabal.mkDerivation (self : { pname = "mtl"; version = "1.1.1.1"; # version of mtl1 compatible with ghc7 sha256 = "157gbrgrg0l9r72nq45dkach53yncysif4qglsaql28g37djc4x6"; meta = { description = "Monad transformer library"; }; })