--- /dev/null
+
+\header {
+
+texidoc = "3 ways to customize ledger line positions."
+
+}
+
+\version "2.19.41"
+\paper { ragged-right = ##t }
+
+\relative {
+ \override Staff.StaffSymbol.ledger-positions = #'(7 10)
+ f''4 g a b c d e f g a b c
+}
+
+\relative {
+ % note: the scheme procedure (lambda expression) is quoted
+ \override Staff.StaffSymbol.ledger-positions-function =
+ #'(lambda (staff-symbol-grob pos) (list pos))
+ c'''4 d e f
+}
+
+\relative {
+ c'''4
+ \once \override NoteHead.ledger-positions = #'(8 10 12 14)
+ d e f
+}