Re: tie over clef change

[Jean Abou Samra]

Le 26/09/2020 à 15:41, Dan Eble a écrit :
> On Sep 26, 2020, at 08:55, Werner LEMBERG <wl@gnu.org> wrote:
> > Despite Gould's “incorrect” verdict, here is an example from an old UE
> > edition of Liszt's “Liebestraum No. 1”, which demonstrates that ties
> > over clef changes *do* happen and make sense sometimes...
> >
> > I still think that LilyPond should support that, handling the tie like
> > a slur in this case.
> That's a very good example.  It's hard to imagine any reasonable alternative.
>
> What kind of grob would an editor expect here? a Tie because it connects notes 
> of the same pitch, or a Slur because it connects notes at different staff 
> positions? (or something else?)

If this were ever implemented, I would expect a Tie.The ~ sign
builds a strong mental connectionwith Tie objects. The different
staff positions are the result ofthe work of the typesetting engine.
In my opinion, the type of agrob should only depend on the input.
Note that having a Slur wouldactually break user code in cases
where the Tie is at the end ofsystem and thus perfectly correct.
Consider:

{
  \override Tie.color = #red
  c'1~
  \clef bass
  \break
  c'1
}

Also, we advocate separation of layout and content. It's
better in my eyes not to silently change the grob type if
a clef change is removed.

That being said, I don't think we should have this as a
default, notably because of the ugly output when the tie
is between chords. As an option, why not. I'm not sure
Joe user would look into the Internals in this case though.
I would just change it to a slur…

Regards,
Jean