+(define-public (make-repeat name times main alts)
+ "create a repeat music expression, with all properties initialized properly"
+ (let ((talts (if (< times (length alts))
+ (begin
+ (ly:warning (_ "More alternatives than repeats. Junking excess alternatives"))
+ (take alts times))
+ alts))
+ (r (make-repeated-music name)))
+ (set! (ly:music-property r 'element) main)
+ (set! (ly:music-property r 'repeat-count) (max times 1))
+ (set! (ly:music-property r 'elements) talts)
+ (if (equal? name "tremolo")
+ (let* ((dot? (zero? (modulo times 3)))
+ (dots (if dot? 1 0))
+ (mult (if dot?
+ (quotient (* times 2) 3)
+ times))
+ (shift (- (ly:intlog2 mult))))
+
+ (if (memq 'sequential-music (ly:music-property main 'types))
+ ;; \repeat "tremolo" { c4 d4 }
+ (let ((children (length (ly:music-property main 'elements))))
+ (if (not (= children 2))
+ (ly:warning (_ "expecting 2 elements for chord tremolo, found ~a") children))
+ (ly:music-compress r (ly:make-moment 1 children))
+ (shift-duration-log r (1- shift) dots))
+ ;; \repeat "tremolo" c4
+ (shift-duration-log r shift dots)))
+ r)))
+