anchor.diff:      fltk
       zlib
       curl
  -    blas
  -    lapack
  +    blas'
  +    lapack'
       libsndfile
       fftw
       fftwSinglePrec
       portaudio
  -    qrupdate
  -    arpack
  +    qrupdate'
  +    arpack'
       libwebp
       gl2ps
     ]
  
positive.code:   passthru = {
      inherit version;
      sitePath = "share/octave/${version}/site";
    };
  
    meta = {
  
negative.code:   ++ stdenv.lib.optionals (ghostscript != null) [ ghostscript ]
    ++ stdenv.lib.optionals (hdf5 != null) [ hdf5 ]
    ++ stdenv.lib.optionals (glpk != null) [ glpk ]
    ++ stdenv.lib.optionals (suitesparse != null) [ suitesparse' ]
    ++ stdenv.lib.optionals (enableJava) [ jdk ]
    ++ stdenv.lib.optionals (sundials_2 != null) [ sundials_2 ]
    ++ stdenv.lib.optionals (gnuplot != null) [ gnuplot ]
  