anchor.diff:      inherit fetchurl stdenv curl openssl zlib expat perl python gettext gnugrep
         asciidoc texinfo xmlto docbook2x docbook_xsl docbook_xml_dtd_45 libxslt
         cpio tcl tk makeWrapper subversion;
  -    svnSupport = config "svnSupport" false; # for git-svn support
  -    guiSupport = config "guiSupport" false;
  -    sendEmailSupport = config "sendEmailSupport" false;
  +    svnSupport = false;		# for git-svn support
  +    guiSupport = false;		# requires tcl/tk
  +    sendEmailSupport = false;	# requires plenty of perl libraries
       perlLibs = [perlPackages.LWP perlPackages.URI perlPackages.TermReadKey];
       smtpPerlLibs = [
         perlPackages.NetSMTP perlPackages.NetSMTPSSL
  
positive.code: args: with args; with pkgs;
  let
    inherit (pkgs) stdenv fetchurl subversion;
    config = param: getConfig [ "git" param ];
  in
  rec {
  
  
negative.code:       asciidoc texinfo xmlto docbook2x
        docbook_xsl docbook_xml_dtd_45 libxslt
        cpio tcl tk makeWrapper subversion autoconf;
      svnSupport = false;
      guiSupport = false;
      perlLibs = [perlPackages.LWP perlPackages.URI perlPackages.TermReadKey subversion];
    };
  
  