Error with empty submenu

[stmllr]

I created a menu with some submenus and one of the submenus subMenuTuner should be empty, having just one item to exit the submenu.

This is how the submenu looks like:

result handleTuner(eventMask event, navNode& nav, prompt &item);

MENU(subMenuTuner,"TUNER",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
  // add menu items here
  ,EXIT("<BACK")
);

However, I end with compiler error:

exit status 1
'subMenuTuner_text' was not declared in this scope

If I add another item to the menu, e.g. OP("foo",doNothing,noEvent) compiler works fine.

What would be an appropriate way to generate an empty submenus?

[stmllr]

compiler output:

~/.arduino15/packages/arduino/tools/avr-gcc/7.3.0-atmel3.6.1-arduino5/bin/avr-g++ -c -g -Os -w -std=gnu++11 -fpermissive -fno-exceptions -ffunction-sections -fdata-sections -fno-threadsafe-statics -Wno-error=narrowing -MMD -flto -mmcu=atmega4809 -DF_CPU=16000000L -DARDUINO=10819 -DARDUINO_AVR_NANO_EVERY -DARDUINO_ARCH_MEGAAVR -DAVR_NANO_4809_328MODE -DMILLIS_USE_TIMERB3 -DNO_EXTERNAL_I2C_PULLUP -I~/.arduino15/packages/arduino/hardware/megaavr/1.8.7/cores/arduino/api/deprecated -I~/.arduino15/packages/arduino/hardware/megaavr/1.8.7/cores/arduino -I~/.arduino15/packages/arduino/hardware/megaavr/1.8.7/variants/nona4809 -I~/.arduino15/packages/arduino/hardware/megaavr/1.8.7/libraries/EEPROM/src -I~/.arduino15/packages/arduino/hardware/megaavr/1.8.7/libraries/Wire/src -I~/Arduino/libraries/Adafruit_ADS1X15 -I~/Arduino/libraries/Adafruit_BusIO -I~/Arduino/libraries/Adafruit_MCP4728 -I~/.arduino15/packages/arduino/hardware/megaavr/1.8.7/libraries/SPI/src -I~/Arduino/libraries/MIDI_Library/src -I~/Arduino/libraries/ArduinoMenu_library/src -I~/Arduino/libraries/U8g2/src -I~/Arduino/libraries/RotaryEncoder/src -I~/Arduino/libraries/Bounce2/src -I~/Arduino/libraries/LinkedList /tmp/arduino_build_31940/sketch/main.ino.cpp -o /tmp/arduino_build_31940/sketch/main.ino.cpp.o
In file included from ~/Arduino/libraries/ArduinoMenu_library/src/menuBase.h:31:0,
                from ~/Arduino/libraries/ArduinoMenu_library/src/menuDefs.h:12,
                from ~/Arduino/libraries/ArduinoMenu_library/src/menu.h:15,
                from ~/tool/src/main/main.ino:8:
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:62:17: error: 'DECL_' does not name a type; did you mean 'DECL'?
#define DECL(x) DECL_##x
                ^
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:9:34: note: in expansion of macro 'DECL'
#define FOR_EACH_1(what, x, ...) what(x)
                                 ^~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:12:3: note: in expansion of macro 'FOR_EACH_1'
  FOR_EACH_1(what,  __VA_ARGS__)
  ^~~~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:7:35: note: in expansion of macro 'FOR_EACH_2'
#define CONCATENATE2(arg1, arg2)  arg1##arg2
                                  ^~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:109:32: note: in expansion of macro 'FOR_EACH_'
#define FOR_EACH(what, x, ...) FOR_EACH_(FOR_EACH_NARG(x, __VA_ARGS__), what, x, __VA_ARGS__)
                               ^~~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:195:3: note: in expansion of macro 'FOR_EACH'
  FOR_EACH(DECL,__VA_ARGS__)\
  ^~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:192:42: note: in expansion of macro 'altMENU'
#define MENU(id,text,aFn,mask,style,...) altMENU(Menu::menu,id,text,aFn,mask,style,(Menu::_menuData|Menu::_canNav),__VA_ARGS__)
                                         ^~~~~~~
~/tool/src/main/tuner.h:3:1: note: in expansion of macro 'MENU'
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
^~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:63:16: error: 'DEF_' was not declared in this scope
#define DEF(x) DEF_##x,
               ^
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:9:34: note: in expansion of macro 'DEF'
#define FOR_EACH_1(what, x, ...) what(x)
                                 ^~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:12:3: note: in expansion of macro 'FOR_EACH_1'
  FOR_EACH_1(what,  __VA_ARGS__)
  ^~~~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:7:35: note: in expansion of macro 'FOR_EACH_2'
#define CONCATENATE2(arg1, arg2)  arg1##arg2
                                  ^~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:109:32: note: in expansion of macro 'FOR_EACH_'
#define FOR_EACH(what, x, ...) FOR_EACH_(FOR_EACH_NARG(x, __VA_ARGS__), what, x, __VA_ARGS__)
                               ^~~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:198:5: note: in expansion of macro 'FOR_EACH'
    FOR_EACH(DEF,__VA_ARGS__)\
    ^~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:192:42: note: in expansion of macro 'altMENU'
#define MENU(id,text,aFn,mask,style,...) altMENU(Menu::menu,id,text,aFn,mask,style,(Menu::_menuData|Menu::_canNav),__VA_ARGS__)
                                         ^~~~~~~
~/tool/src/main/tuner.h:3:1: note: in expansion of macro 'MENU'
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
^~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:63:16: note: suggested alternative: 'DEF'
#define DEF(x) DEF_##x,
               ^
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:9:34: note: in expansion of macro 'DEF'
#define FOR_EACH_1(what, x, ...) what(x)
                                 ^~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:12:3: note: in expansion of macro 'FOR_EACH_1'
  FOR_EACH_1(what,  __VA_ARGS__)
  ^~~~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:7:35: note: in expansion of macro 'FOR_EACH_2'
#define CONCATENATE2(arg1, arg2)  arg1##arg2
                                  ^~~~
~/Arduino/libraries/ArduinoMenu_library/src/baseMacros.h:109:32: note: in expansion of macro 'FOR_EACH_'
#define FOR_EACH(what, x, ...) FOR_EACH_(FOR_EACH_NARG(x, __VA_ARGS__), what, x, __VA_ARGS__)
                               ^~~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:198:5: note: in expansion of macro 'FOR_EACH'
    FOR_EACH(DEF,__VA_ARGS__)\
    ^~~~~~~~
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:192:42: note: in expansion of macro 'altMENU'
#define MENU(id,text,aFn,mask,style,...) altMENU(Menu::menu,id,text,aFn,mask,style,(Menu::_menuData|Menu::_canNav),__VA_ARGS__)
                                         ^~~~~~~
~/tool/src/main/tuner.h:3:1: note: in expansion of macro 'MENU'
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
^~~~
In file included from ~/Arduino/libraries/ArduinoMenu_library/src/menuBase.h:31:0,
                from ~/Arduino/libraries/ArduinoMenu_library/src/menuDefs.h:12,
                from ~/Arduino/libraries/ArduinoMenu_library/src/menu.h:15,
                from ~/tool/src/main/main.ino:8:
tuner.h:3:6: error: 'subMenuTuner_text' was not declared in this scope
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
     ^
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:203:5: note: in definition of macro 'altMENU'
    id##_text,\
    ^~
~/tool/src/main/tuner.h:3:1: note: in expansion of macro 'MENU'
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
^~~~
~/tool/src/main/tuner.h:3:6: note: suggested alternative: 'subMenuTuner_data'
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
     ^
~/Arduino/libraries/ArduinoMenu_library/src/macros.h:203:5: note: in definition of macro 'altMENU'
    id##_text,\
    ^~
~/tool/src/main/tuner.h:3:1: note: in expansion of macro 'MENU'
MENU(subMenuTuner,"EMPTY SUBMENU",handleTuner,(Menu::eventMask)(enterEvent|exitEvent),wrapStyle
^~~~

[neu-rah]

correct, macros require a menu with at least 2 elements.