- (barNumberVisibility ,procedure? "A Procedure that takes an
-integer and returns whether the corresponding bar number should be
-printed.")
+ (barNumberFormatter ,procedure? "A procedure that takes a bar
+number, measure position, and alternative number and returns a markup
+of the bar number to print.")
+ (barNumberVisibility ,procedure? "A procedure that takes a bar
+number and a measure position and returns whether the corresponding
+bar number should be printed.")