(list part1 part2) DOWN chord-range))
partcombineForce =
-#(define-music-function (location parser type once) (symbol-or-boolean? boolean?)
+#(define-music-function (location parser type once) (boolean-or-symbol? boolean?)
(_i "Override the part-combiner.")
(make-music 'EventChord
'elements (list (make-music 'PartCombineForceEvent