+ (meta . ,(grob-description "Dots" font-interface dots-interface ))
+ ))
+ (DoublePercentRepeat
+ . ((molecule-callback . ,Percent_repeat_item_interface::double_percent)
+ (breakable . #t)
+ (slope . 1.0)
+ (font-family . music)
+ (width . 2.0)
+ (thickness . 0.48)
+ (break-align-symbol . Staff_bar)
+ (visibility-lambda . ,begin-of-line-invisible)
+ (meta . ,(grob-description "DoublePercentRepeat" font-interface percent-repeat-interface))
+ ))