Dear Cynthia, thank you for your help!
What you propose works correctly but it is not practical. I use tag to avoid duplicating code so it is crucial to be able to do not create two different variables music_screenOut and music_midiOut. Thank you, g. _______________________________________________ lilypond-user mailing list lilypond-user@gnu.org https://lists.gnu.org/mailman/listinfo/lilypond-user