On 2020-01-21 7:02 pm, Kieren MacMillan wrote:
HOLD THE PRESSES!!I think I have it: %%%% SNIPPET BEGINS \version "2.19.83" some-music = { a'4 bes' b' aes' g' cis' d' ees' fis' f' e' c' } #(define-markup-list-command (diffints layout props mus) (ly:music?) (interpret-markup-list layout props (map (lambda (d) (string-append (if (positive? d) "+" "") (number->string d))) (let ((muspst (map ly:pitch-semitones (music-pitches mus)))) (map - (cdr muspst) muspst))))) \markup \line \with-color #red \diffints #some-music \markup \line \with-color #red \diffints ##{ c' d' e' c' #} %%%% SNIPPET ENDS Comments and code critique appreciated.
Instead of string-append and number->string, try (format #f "~@d" d). ~d formats an integer as a decimal value @ includes "+" for positive values One caveat is it formats zero as "+0". Perhaps: (lambda (d) (if (zero? d) "0" (format #f "~@d" d))) -- Aaron Hill
