Re: conditional parenthesis

Am Sa., 4. Juli 2026 um 07:50 Uhr schrieb Walt North <[email protected]>:
>
> I have a case where I need to put parenthesis around some notes (not all notes) for a given instrument to emphasize a specific thing at certain points.
>
> I thought this might be a case where tags would come in handy.
>
> But the following doesn't add the parenthesis. What am I missing?  Is the problem related to having tags within a function? Or would there be a better way to do this.
>
> \version "2.26.0"
>
> par = #(define-music-function (note) (ly:music?)
>    #{
>    \tag #'(piano)  { #note }
>    \tag #'(guitar)  { \parenthesize #note }
>    #})
>
> music = {c'1}
>
> \score {
>   {
>     \keepWithTag #'piano {\par \music}
>   }
> }
> \score {
>   {
>     \keepWithTag #'guitar {\par \music}
>   }
> }
>
>

Two issues:
a)
\parenthesize works on a single note or event-chord.
Your `music` is sequential music, though.
Thus {  \parenthesize { c'1 } } does not work.
b)
In the function you do #note. This _changes_ `note` for all instances
of the function.
Use a copy instead, i.e. $note

As long as you only want to parenthesize single notes below works here:

par = #(define-music-function (note) (ly:music?)
   #{
   \tag #'(piano)  { $note }
   \tag #'(guitar)  { \parenthesize $note }
   #})

music = c'1

\score {
  {
    \keepWithTag #'piano {\par \music}
  }
}
\score {
  {
    \keepWithTag #'guitar {\par \music}
  }
}


Cheers,
  Harm