Hello Jean and Thomas,
Thank you -- both solutions are insightful and useful in future solutions.
I did not know about empty stencils, and I read about a void-function
earlier, but was not entirely sure how to utilize it.
Many thanks,
mattfong
On Sat, Oct 17, 2020 at 10:49 AM Thomas Morley <thomasmorle...@gmail.com>
wrote:
> Am Sa., 17. Okt. 2020 um 19:39 Uhr schrieb Jean Abou Samra <
> j...@abou-samra.fr>:
> >
> > Hi,
> >
> > Le 17/10/2020 à 19:27, Matthew Fong a écrit :
> >
> > > Hello Richard,
> > >
> > > I just discovered your explanation is in fact the case, and also
> > > concluded cond wouldn't work either.
> > >
> > > I might have to settle for an empty markup block for now.
> >
> > The point of interpret-markup is to turn a markup into a stencil, so I'd
> > use empty-stencil:
> >
> > \version "2.20.0"
> >
> > #(define-markup-command (print-if-defined layout props sym text)
> > (symbol? markup?)
> > (if (defined? sym)
> > (interpret-markup layout props
> > #{ \markup \with-color #'(0.8 0.2 0.2) #text #})
> > empty-stencil))
> >
> > symA = "Something"
> >
> > \markup {
> > \print-if-defined #'symA "Text"
> > \print-if-defined #'symB "More text"
> > }
> >
> > Best,
> > Jean
> >
> >
>
> An empty stencil will still be spaced (unless removed by other
> markup-commands).
> Why not a void-function?
>
> print-if-defined =
> #(define-void-function (sym text) (symbol? markup?)
> (if (defined? sym)
> (add-text #{ \markup \with-color #'(0.8 0.2 0.2) #text #})))
>
> symA = "Something"
>
> \print-if-defined #'symB "Text"
> \print-if-defined #'symA "Text"
>
> Cheers,
> Harm
>
