variant_group "desktop-environment" do variant "kde" variant "gnome" end variant_group "debug" do variant "debug" variant "release" end with_variants do env "prog" do |env| if variant("kde") env["CPPDEFINES"] << "KDE" end if variant("gnome") env["CPPDEFINES"] << "GNOME" end if variant("debug") env["CPPDEFINES"] << "DEBUG" end if variant("release") env["CPPDEFINES"] << "NDEBUG" end env.Program("^/prog.exe", "prog.c") end end