- (cond
- ((equal? number-type 'roman-lower)
- (fancy-format #f "~(~@r~)" base-fret))
- ((equal? number-type 'roman-upper)
- (fancy-format #f "~@r" base-fret))
- ((equal? 'arabic number-type)
- (fancy-format #f "~d" base-fret))
- ((equal? 'custom number-type)
- (fancy-format #f
- (assoc-get 'fret-label-custom-format
- details "~a")
- base-fret))
- (else (fancy-format #f "~(~@r~)" base-fret))))