anchor.diff:  { stdenv, fetchurl, ghostscript, texinfo, imagemagick, texi2html, guile
   , python, gettext, flex, perl, bison, pkgconfig, texLive, dblatex
  -, fontconfig, freetype, pango, fontforge, help2man, zip, netpbm, groff 
  +, fontconfig, freetype, pango, fontforge, help2man, zip, netpbm, groff
   , fetchsvn, makeWrapper }:
   
   stdenv.mkDerivation rec{
  
positive.code:       fontforge help2man groff makeWrapper
      ];
  
    meta = { 
      description = "Music typesetting system";
      homepage = http://lilypond.org/;
      license = "GPL";
  
negative.code:   '';
  
    postInstall = ''
      for f in "$out/bin/"*; do
          wrapProgram "$f" --set GUILE_AUTO_COMPILE 0 \
                           --set PATH "${ghostscript}/bin"
      done
  