(ly:warning (_ "Error in beam quanting. Expected ~S 0, found ~S.")
(procedure-name comparison) slope-sign)
(set! (ly:grob-property beam 'annotation)
(ly:warning (_ "Error in beam quanting. Expected ~S 0, found ~S.")
(procedure-name comparison) slope-sign)
(set! (ly:grob-property beam 'annotation)