Re: Dot-separated list as music function argument

[Thomas Morley]

2014-07-08 13:39 GMT+02:00 Simon Albrecht <address@hidden>:
> Hello everybody,
>
> I just wrote a music function to mark grobs as editorial addition by
> colouring them grey. See the code and an example:
>
> \version "2.19.8"
>
>
> ed = #(let
>
> ((string-or-list?
>
> (lambda (grob)
>
> (or (string? grob)
>
> (list? grob)))))
>
> (define-music-function
>
> (parser location grob mus)
>
> (string-or-list? ly:music?)
>
> #{ \override $grob . color = #(x11-color 'grey40)
>
> $mus
>
> \revert $grob . color #}
>
> )
>
> )
>
>
> \relative { \ed NoteHead c' \ed #'(Staff Accidental) { cis dis } es }
>
>
> %%%%%%%%%%%%%
>
>
> The 2.18 changes document says that #'(Staff Accidental) and
> Staff.Accidental were now interchangeable, however if I replace it in the
> second function call, I get errors (unexpected "." etc.). Is there a way to
> avoid this in the coding of the function or should it be considered a bug?
>
> Best regards,
> Simon


Hi,

use the predicate symbol-list-or-symbol?
Below a working version, displaying some info as well:

\version "2.19.8"

ed =
#(define-music-function (parser location grob mus)
  (symbol-list-or-symbol? ly:music?)
;; displaying some info:
    (format #t "\nI'm the list: \t\t\t~a
My first entry is:          \t~a
My next entry is:           \t~a
My first entry is a symbol? \t~a
My next entry is a symbol?  \t~a"
               grob
               (car grob)
               (if (not (null? (cdr grob)))
                   (cadr grob)
                   "none")
               (symbol? (car grob))
               (if (not (null? (cdr grob)))
                   (symbol? (cadr grob))
                   "none found"))
    (newline)
;; coloring the grob(s)
    #{
      \override $grob . color = #(x11-color 'grey40)
      $mus
      \revert $grob . color
    #})


\relative { \ed NoteHead c' \ed #'(Staff Accidental) { cis dis } es }
\relative { \ed NoteHead c' \ed Staff.Accidental { cis dis } es }

HTH,
  Harm