{ mkDerivation, attoparsec, base, stdenv }:
mkDerivation {
  pname = "attoparsec-expr";
  version = "0.1.1.2";
  sha256 = "deadbeef";
  libraryHaskellDepends = [ attoparsec base ];
  description = "Port of parsec's expression parser to attoparsec";
  license = stdenv.lib.licenses.bsd3;
}