anchor.diff:      RM=$(type -tp rm)
       substituteInPlace configure --replace "/bin/uname" "$UNAME"
       substituteInPlace tools/beautify-archive --replace "/bin/rm" "$RM"
  -    substituteInPlace Makefile.build --replace "ifeq (\$(ARCH),Darwin)" "ifeq (\$(ARCH),Darwinx)"
  +    substituteInPlace configure.ml --replace "if arch = \"Darwin\" then \"md5" "if arch = \"Darwinx\" then \"md5"
       ${csdpPatch}
     '';
   
  
positive.code:   inherit ocaml camlp5;
  
    src = fetchurl {
      url = https://coq.inria.fr/distrib/V8.5beta2/files/coq-8.5beta2.tar.gz;
      sha256 = "1z34ch56lld86srgsjdwdq3girz0k0wqmvyxsa7jwvvxn3qmmq2v";
    };
  
    buildInputs = [ pkgconfig ocaml findlib camlp5 ncurses lablgtk ];
  
negative.code: {stdenv, fetchurl, writeText, pkgconfig, ocaml, findlib, camlp5, ncurses, lablgtk ? null, csdp ? null}:
  
  let
    version = "8.5rc1";
    coq-version = "8.5";
    buildIde = lablgtk != null;
    ideFlags = if buildIde then "-lablgtkdir ${lablgtk}/lib/ocaml/*/site-lib/lablgtk2 -coqide opt" else "";
  