Jean,
Merci
This is a perfect solution, and, a clear explanation about why my solution
failed.
Thank you very much
Ken Ledeen
Mobile: 617-817-3183
www.nevo.com
www.bitsbook.com
tiny.cc/KenLedeen
tiny.cc/KenLedeenAmazon
ᐧ
On Sat, Feb 27, 2021 at 10:43 AM Jean Abou Samra <j...@abou-samra.fr> wrote:
> Le 27/02/2021 à 02:16, Ken Ledeen a écrit :
>
> > I am struggling to understand the restrictions on substitution functions.
> >
> > For example:
> >
> > 1) can a function include "\score { ...}" or can it only be invoked
> > INSIDE a \score?
> >
> > 2) is it possible to include \header { ...} inside a substitution
> > function? It fails when I try, but I don't understand why.
> >
> > I assume I am missing some basic concepts regarding their use.
> >
> > Thanks!
>
>
> Hello,
>
> Music functions must return music objects; \score blocks are not music
> but general containers that enclose music as well as other objects such
> as \header and \layout blocks.
>
> However, replacing define-music-function with define-scheme-function,
> you can define more versatile functions that are allowed to return any
> kind of object for interpretation. For example:
>
> \version "2.23.1"
>
> failingFunction =
> #(define-music-function () ()
> #{
> \score {
> \header {
> piece = "Piece A"
> }
> { c' }
> }
> #})
>
> % \failingFunction
>
> succeedingFunction =
> #(define-scheme-function () ()
> #{
> \score {
> \header {
> piece = "Piece B"
> }
> { c' }
> }
> #})
>
> \succeedingFunction
>
>
> Hope that helps,
> Jean
>
>
