optional_depends  xorg-libs                \
                  ""                      \
                  ""                      \
                  "for X-based GUI tool"  &&

optional_depends  tcl                             \
                  "--with-tcl"                    \
                  "--without-tcl"                 \
                  "for Tcl scripting components"  &&

optional_depends  tk                             \
                  "--with-tk"                    \
                  "--without-tk"                 \
                  "for Tk scripting components"
