anchor.diff:      owner = "c-cube";
       repo = "ocaml-containers";
       rev = "${version}";
  -    sha256 = "1mc33b4nvn9k3r4k56amxr804bg5ndhxv92cmjzg5pf4qh220c2h";
  +    sha256 = "169j8vqg8h70wbldjg610jqikfk23ggw8zypmpzv3piym5p1dfiw";
     };
   
  -  buildInputs = [ ocaml findlib cppo gen sequence qtest ounit ocaml_oasis ];
  +  buildInputs = [ ocaml findlib cppo gen sequence qtest ounit ocaml_oasis qcheck ];
   
     propagatedBuildInputs = [ result ];
   
  
positive.code:     let v = stdenv.lib.getVersion ocaml; in
        "${p}/lib/ocaml/${v}/site-lib";
  
    version = "0.16";
  
  in
  
  
negative.code: { stdenv, fetchFromGitHub, ocaml, findlib, cppo, gen, sequence, qtest, ounit, ocaml_oasis, result
  , qcheck }:
  
  let
  
  