anchor.diff:          };
       in
         import ./bash-4.3-patches.nix patch) 
  -      ++ stdenv.lib.optional stdenv.isCygwin ./cygwin-bash-4.3.33-1.src.patch;
  +      ++ optional stdenv.isCygwin ./cygwin-bash-4.3.33-1.src.patch;
   
     crossAttrs = {
       configureFlags = baseConfigureFlags +
         " bash_cv_job_control_missing=nomissing bash_cv_sys_named_pipes=nomissing" +
  -      stdenv.lib.optionalString stdenv.isCygwin ''
  +      optionalString stdenv.isCygwin ''
           --without-libintl-prefix --without-libiconv-prefix
           --with-installed-readline
           bash_cv_dev_stdin=present
           bash_cv_dev_fd=standard
  -        bash_cv_termcap_lib=libncurses 
  +        bash_cv_termcap_lib=libncurses
         '';
     };
   
  
positive.code: 
    # Note: Bison is needed because the patches above modify parse.y.
    nativeBuildInputs = [bison]
      ++ stdenv.lib.optional (texinfo != null) texinfo
      ++ stdenv.lib.optional interactive readline
      ++ stdenv.lib.optional stdenv.isDarwin binutils;
  
    # Bash randomly fails to build because of a recursive invocation to
    # build `version.h'.
    enableParallelBuilding = false;
  
    postInstall = ''
      # Add an `sh' -> `bash' symlink.
      ln -s bash "$out/bin/sh"
    ''
      # most space is taken by locale data
      + stdenv.lib.optionalString (!interactive) ''
        rm -r "$out/share"
      '';
  
    meta = {
      homepage = http://www.gnu.org/software/bash/;
      description =
        "GNU Bourne-Again Shell, the de facto standard shell on Linux" +
  
negative.code:   shortName = "bash43";
    baseConfigureFlags = if interactive then "--with-installed-readline" else "--disable-readline";
    sha256 = "1m14s1f61mf6bijfibcjm9y6pkyvz6gibyl8p4hxq90fisi8gimg";
  
    inherit (stdenv.lib) optional optionalString;
  in
  
  stdenv.mkDerivation rec {
  