Thanks for your response Jean, So, the music notation system I am writing has assimetrical staves with only 4 lines, which means there is a blank space wider than the other two white spaces. For notes that fall into the wider blank space, I want a ledger line value of 2, but for the note that falls into the narrower blank space (G) I want a ledger line value of 1. From what you say, I believe you are worried about chords, am I right? In that case it would depend on whether the highest note is a G if it is above the staff or if the lowest is a G if it is below the staff.
Robert El vie, 13 oct 2023 a las 16:38, Jean Abou Samra (<j...@abou-samra.fr>) escribió: > Le vendredi 13 octobre 2023 à 15:36 +0200, Robert Mengual a écrit : > > In the example below, I am receiving the following error: Wrong type > argument in position 1 (expecting Stream_event): #f > > I think I am not receiving a grob in this case. > > > > You are, but this grob doesn't have an event cause. The event-cause > function returns either a stream event, or #f if the grob doesn't have a > stream event cause (the boolean false, #f, is traditionally used in Scheme > for missing values, where many other languages would use some value called > null, nil, None, undefined, ...). > > How could I move forward with this? The use case is very simple, if the > note is a G I want to return a 1 and if not I want to return a 2. > > > > I don't really understand what you're trying to do. A StaffSymbol spans > the whole score. What do you do if there are both G notes and other notes? > > Do you want to adjust ledger lines locally, for each note? This is rather > complicated to do, though there are hacks for that. >
