Re: Cello fingering indications

[David Kastrup]

MarcM <address@hidden> writes:

> This function apparently worked in version 2.14. 
> I tried in 2.18 and the line is not printed so the change is not due to a
> recent commit.
>
> I just want to implement a simple function for the music directive "restez"
> (*) which is usually indicated with the text "restez" and a line that spans
> a list of notes.
>
> (*) restez [French] 
> A directive to the performer of a stringed instrument to perform the
> indicated passage of a composition remaining on he same note, on the same
> string or in the same finger position. 
> http://dictionary.onmusic.org/terms/2880-restez

The old code presents a few other challenges to convert-ly (it converts
anything containing ly:export to a version using $(...) instead of
#(...) and that goes wrong in this case), but it's essentially issue
2240 and would (after changing $ back to #), as stated previously, yield
to using event-chord-wrap!  at the start of the music function.

At any rate, here is a "nice" version without such workarounds.
add-event seems to be a frequent enough use case to figure out a nice
global name for it and provide it in LilyPond proper.

 \version "2.18.0"

stringNumberSpanner =
#(define-music-function (parser location StringNumber music)
   (markup? ly:music?)
   (define (add-event mus event)
     (let ((prop (if (music-is-of-type? mus 'rhythmic-event)
                     'articulations 'elements)))
       (set! (ly:music-property mus prop)
             (append (ly:music-property mus prop) (list event)))))
   (let ((elts (extract-typed-music music '(rhythmic-event event-chord))))
     (if (pair? elts)
         (begin
           (add-event (first elts)
                      #{
                        \tweak style #'solid
                        \tweak font-size #-5
                        \tweak bound-details.left.stencil-align-dir-y #CENTER
                        \tweak bound-details.left.text
                           \markup { \circle \number $StringNumber }
                        \startTextSpan
                      #})
           (add-event (last elts) #{ \stopTextSpan #}))))
   music)

\relative c {
 \clef "treble_8"
 \textSpannerDown
 \stringNumberSpanner "5" { a8 b c d e f }
 \stringNumberSpanner "4" { g a bes4 a g2 }
}

-- 
David Kastrup