+markLengthOn = {
+ \override Score.MetronomeMark.extra-spacing-width = #'(0 . 1.0)
+ \override Score.RehearsalMark.extra-spacing-width = #'(-0.5 . 0.5)
+ % Raise as much as four staff-spaces before pushing notecolumns right
+ \override Score.MetronomeMark.extra-spacing-height = #'(4 . 4)
+ \override Score.RehearsalMark.extra-spacing-height = #'(4 . 4)
+}
+
+markLengthOff = {
+ \override Score.MetronomeMark.extra-spacing-width = #'(+inf.0 . -inf.0)
+ \override Score.RehearsalMark.extra-spacing-width = #'(+inf.0 . -inf.0)
+ \revert Score.MetronomeMark.extra-spacing-height
+ \revert Score.RehearsalMark.extra-spacing-height
+}