optional_depends  g++                      \
                  ""                       \
                  ""                       \
                  "for a c++ library"      &&

optional_depends  libusb                   \
                  "--enable-libusb"        \
                  "--disable-libusb"       \
                  "Enable use of libusb"   &&

optional_depends  libpng                   \
                  "--with-png=/usr/lib"    \
                  "--without-png"          \
                  "Enable PNG Support"     &&

optional_depends  perl                     \
                  "--with-perl"            \
                  "--without-perl"         \
                  "Enable Perl Support"    &&

optional_depends  JDK                      \
                  '--with-java'            \
                  '--without-java'         \
                  'Enable Java Support'    \
                  'z-rejected'             &&

optional_depends  python                   \
                  "--with-python"          \
                  "--without-python"       \
                  "Enable Python Support"  &&

optional_depends  tk                       \
                  "--with-tcl=/usr/lib --with-tclinclude=/usr/include"  \
                  "--without-tcl"          \
                  "Enable TCL Support"     
