anchor.diff:  , bison
   , fetchurl
   , flex
  +, lib
   }:
   
   let
  -  inherit (stdenv.lib)
  +  inherit (lib)
       replaceChars;
   
  -  version = "2017-11-10";
  +  version = "2018-01-05";
     version' = replaceChars ["-"] [""] version;
   in
   stdenv.mkDerivation rec {
  
positive.code: 
    src = fetchurl {
      url = "https://acpica.org/sites/acpica/files/acpica-unix-${version'}.tar.gz";
      multihash = "QmdYk4mcdETNo9jVzJdjhEwrbkREWGC2bbyFySLsFojNAz";
      sha256 = "56ac1f870db698fc46f9be0698abe6f4b5bf189bfb12cf982302c0a8f920856a";
    };
  
    nativeBuildInputs = [
  
negative.code:     install generate/unix/bin*/iasl $out/bin
    '';
  
    meta = with lib; {
      description = "Intel ACPI Compiler";
      homepage = http://www.acpica.org/;
      license = licenses.iasl;
  