anchor.diff:            ''-${lib.optionalString (cups == null) "no-"}cups''
             "-dbus-linked"
             "-glib"
  +        ]
  +        ++ lib.optional (compareVersion "5.15.0" < 0) "-system-libjpeg"
  +        ++ [
             "-system-libpng"
           ]
           ++ lib.optional withGtk3 "-gtk"
  
positive.code:       ''-${lib.optionalString (!buildExamples) "no"}make examples''
        ''-${lib.optionalString (!buildTests) "no"}make tests''
      ]
  
      ++ (
        if stdenv.isDarwin
  
negative.code:       else
          [
            "-${lib.optionalString (compareVersion "5.9.0" < 0) "no-"}rpath"
          ]
          ++ lib.optional (compareVersion "5.15.0" < 0) "-system-xcb"
          ++ [
            "-xcb"
            "-qpa xcb"
            "-L" "${libX11.out}/lib"
  