Re: calling a music variable using a Scheme function

[Nicolas Sceaux]

Le 19 déc. 08 à 14:12, Valentin Villenave a écrit :

> Greetings Nicolas, hi everybody,
>
> can someone tell me why the following snippet doesn't work?
> (It's heavily based on Nicolas' functions -- and looked sooo  
> promising...)
>
> %%%%%%%%%%%
> #(use-modules (ice-9 format))
>
> toto = { c d c d }
>
> includevar=
> #(define-music-function (parser location name) (string?)
>   (ly:parser-parse-string
>     (ly:parser-clone parser)
>     (format #f "\\~a"
>             name))
>   (make-music 'SequentialMusic 'void #t))
>
> { e1 \includevar #"toto" }

"Il y avait plus simple" (cf Bertrand Renard)

includeVar =
#(define-music-function (parser location name) (string?)
   (let ((music (ly:parser-lookup parser (string->symbol name))))
     (if (ly:music? music)
         music
         (make-music 'Music 'void #t))))

Your function does not work as you expect because it just returns an
empty SequentialMusic. Only the return value of the music function gets
"inserted" in the current music. Read scm/parser-ly-from-scheme.scm,
function parse-string-result.

Nicolas