Coloring notes depending on their pitch (alternate version)

It is possible to color note heads depending on their pitch and/or their names: the function used in this example even makes it possible to distinguish enharmonics.

This is an alternate version of the original snippet found here: http://lsr.di.unimi.it/LSR/Item?id=572 This version achieves the same result by using different code that some may find easier to understand. (It uses case rather than an association list to assign the colors.)

\version "2.24.0"

%%http://lsr.di.unimi.it/LSR/Item?id=897

#(define (color-notehead grob)
   (let* ((pch (ly:event-property (event-cause grob) 'pitch))
          (nnm (ly:pitch-notename pch))
          (alt (ly:pitch-alteration pch)))
          (case nnm
                 ((0) (case alt
                        ((-1) red) ;; Cbb
                        ((-1/2) red) ;; Cb
                        ((0) red) ;; C
                        ((1/2) red) ;; C#
                        ((1) red) ;; C##
                        (else black)))
                 ((1) (case alt
                        ((-1) (x11-color 'orange)) ;; Dbb
                        ((-1/2) (x11-color 'orange)) ;; Db
                        ((0) (x11-color 'orange)) ;; D
                        ((1/2) (x11-color 'orange)) ;; D#
                        ((1) (x11-color 'orange)) ;; D##
                        (else black)))
                 ((2) (case alt
                        ((-1) yellow) ;; Ebb
                        ((-1/2) yellow) ;; Eb
                        ((0) yellow) ;; E
                        ((1/2) yellow) ;; E#
                        ((1) yellow) ;; E##
                        (else black)))
                 ((3) (case alt
                        ((-1) green) ;; Fbb
                        ((-1/2) green) ;; Fb
                        ((0) green) ;; F
                        ((1/2) green) ;; F#
                        ((1) green) ;; F##
                        (else black)))
                 ((4) (case alt
                        ((-1) blue) ;; Gbb
                        ((-1/2) blue) ;; Gb
                        ((0) blue) ;; G
                        ((1/2) blue) ;; G#
                        ((1) blue) ;; G##
                        (else blue)))
                 ((5) (case alt
                        ((-1) (x11-color 'purple)) ;; Abb
                        ((-1/2) (x11-color 'purple)) ;; Ab
                        ((0) (x11-color 'purple)) ;; A
                        ((1/2) (x11-color 'purple)) ;; A#
                        ((1) (x11-color 'purple)) ;; A##
                        (else black)))
                 ((6) (case alt
                        ((-1) (x11-color 'brown)) ;; Bbb
                        ((-1/2) (x11-color 'brown)) ;; Bb
                        ((0) (x11-color 'brown)) ;; B
                        ((1/2) (x11-color 'brown)) ;; B#
                        ((1) (x11-color 'brown)) ;; B##
                        (else black)))
                 (else black))))

\score {
  \new Staff \relative c' {
    \override NoteHead.color = #color-notehead
    c8 b d dis ees f g aes
  }
}