replace-lengths-of-a-pitch-sequence

(defun replace-lengths-of-a-pitch-sequence (omn-list pitch-list length-list)
  (flatten 
   (loop 
     with cnt = 0
     for i in (single-events omn-list)
     
     when (equal (cadr i) (nth cnt pitch-list))
     collect (append  (list (nth cnt length-list)) (rest i)) 
     and do (incf cnt)
     else collect i
     
     when (= cnt (length pitch-list))
     do (setf cnt 0))))



(setf white-series-l (vector-to-pitch '(c4 c5)
                     (gen-white-noise 100 :type :logistic :seed 23)))

(replace-lengths-of-a-pitch-sequence
 (cons 't white-series-l)
 '(e4 f4 a4 gs4 g4 b4 c5 bb4)
 '(2/16 3/16 4/16 5/16 6/16 7/16 8/16))

=> '(t gs4 mf t g4 mf t g4 mf t c5 mf t g4 mf t gs4 mf 1/8 e4 mf 3/16 f4 mf t gs4 mf t gs4 mf t bb4 mf t gs4 mf t fs4 mf t fs4 mf t f4 mf t g4 mf t bb4 mf t b4 mf t b4 mf t g4 mf t e4 mf t g4 mf t fs4 mf t b4 mf 1/4 a4 mf t g4 mf t g4 mf t a4 mf t b4 mf t fs4 mf t bb4 mf t a4 mf 5/16 gs4 mf t a4 mf 3/8 g4 mf t a4 mf t a4 mf t a4 mf t a4 mf t a4 mf t f4 mf t bb4 mf t g4 mf t fs4 mf 7/16 b4 mf t a4 mf t g4 mf t bb4 mf t a4 mf t gs4 mf t a4 mf t gs4 mf t g4 mf t g4 mf t gs4 mf t a4 mf t f4 mf t f4 mf t bb4 mf t gs4 mf t fs4 mf t a4 mf t g4 mf t a4 mf t g4 mf t gs4 mf t bb4 mf t eb4 mf t bb4 mf t fs4 mf t fs4 mf t gs4 mf t g4 mf t gs4 mf t gs4 mf t c4 mf t gs4 mf t g4 mf t gs4 mf 1/2 c5 mf bb4 mf t gs4 mf t fs4 mf t fs4 mf t bb4 mf t a4 mf t g4 mf t g4 mf t b4 mf t g4 mf t f4 mf t g4 mf t gs4 mf t gs4 mf t gs4 mf t gs4 mf t fs4 mf t gs4 mf t eb4 mf t a4 mf)