Re: \oneVoice and \voiceXX commands having the wrong scope

[Mats Bengtsson]

Hackers: Is my guess below correct? In that case, wouldn't it be better
to change the routine that invents new context identifiers so it never
gives the names "1", ..., "4"?

Yuval Harel wrote:
> On Wed, 26 Jan 2005 10:19:54 +0100, Mats Bengtsson  
> <address@hidden> wrote:
>
> > I think you have not fully realized how <<{...} \\ {...}>> works.
> > Your first example is equivalent to
> >
> > \new Staff {
> >      \clef bass
> >      \context Voice="1" {
> >          \oneVoice
> >          c'2-\markup {\column < "oneVoice" "(This markup generates a  
> > programming  error)">} r2 |
> >          << \context Voice = "1" {\voiceOne b2-"Polyphony" r2}
> >             \context Voice = "2" {\voiceTwo g2 r2} >>
> >          c'2-"oneVoice should still be in effect here." r2 |
> >      } |
> > }
> >
> > Since you have the same name "1" for your main voice as is implicitly
> > given to the upper voice by <<{...} \\ {...}>> and since a context is
> > uniquely determined by its name, they are actually the same voice, so
> > any setting that is done within the upper voice of the
> > <<{...} \\ {...}>> will remain after the polyphonal part.
>
>
> OK, that makes sense. I expected the \voiceOne to end when it reaches 
> "}",  but I
> realize now that would prevent declaring variables like {\voiceOne  
> \tieDown} etc.
> I still don't understand the second example - the outer voice is not 
> named  "1" here,
> and still the changes in voice "1" take effect in the outer voice. Is 
> this  the
> correct behavior too?

I guess what happens is the following: When LilyPond creates a voice
context to handle the notes, it invents a name for it. My guess is
that it actually gives it the name "1" (since it's the first Voice
context in the score), which explains the behaviour.

    /Mats

> > Of course, if you give another name than "1" to your main Voice context,
> > your examples will work as you expect.
>
>
> I usually use \context Voice="1" {\oneVoice ...} when there are many  
> polyphonic
> moments in the music. I've found it makes notation simpler when there 
> is  one main
> voice, with some other voices occasionally appearing - I don't have to  
> notate in
> an unnatural way when I want ties and slurs going in and out of these  
> polyphonic
> moments.
> I think I'll try getting along without it now that I'm aware of this  
> complication.
>
> Yuval
>
> >     /Mats
> >
> > Yuval Harel wrote:
> >
> > > \oneVoice scope too short:
> > > ==========================
> > >  \version "2.4.2"
> > >  \new Staff {
> > >     \clef bass
> > >     \context Voice="1" {
> > >         \oneVoice
> > >         c'2-\markup {\column < "oneVoice" "(This markup generates a  
> > > programming  error)">} r2 |
> > >         << {b2-"Polyphony" r2} \\ {g2 r2} >>
> > >         c'2-"oneVoice should still be in effect here." r2 |
> > >     } |
> > > }
> > >  \voiceOne scope too long:
> > > =========================
> > >  \version "2.4.2"
> > >  \new Staff {
> > >     \clef bass
> > >     c'2 r2    |    % commenting out this line eliminates the problem
> > >     << {\voiceOne r1-"voiceOne"} >> |
> > >     c'2-"voiceOne is still in effect" r2
> > >     \oneVoice
> > >     r1-\markup {\column <"oneVoice" "(This markup generates a  
> > > programming  error)">} |
> > > }
> > >  On Wed, 26 Jan 2005 00:22:14 +0100, Erik Sandberg   
> > > <address@hidden> wrote:
> > >
> > > > On Tuesday 25 January 2005 15.03, Yuval Harel wrote:
> > > >
> > > > > Hi,
> > > > >
> > > > > I found that \oneVoice and \voiceOne sometimes have unexpected  
> > > > > effects.
> > > > > Here are two examples which might be two separate bugs.
> > > > > When preparing the examples I also noticed that adding markup can
> > > > > sometimes generate programming errors in these
> > > > > situations.
> > > >
> > > >
> > > >
> > > > The mailing list strips attachments. Could you please resend it,  
> > > > pasted  into
> > > > the message?
> > > >
> > > > Erik
> > >       _______________________________________________
> > > lilypond-user mailing list
> > > address@hidden
> > > http://lists.gnu.org/mailman/listinfo/lilypond-use
> > > r
>
>
>
>
>
> _______________________________________________
> lilypond-user mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/lilypond-use
> r

--
=============================================
        Mats Bengtsson
        Signal Processing
        Signals, Sensors and Systems
        Royal Institute of Technology
        SE-100 44  STOCKHOLM
        Sweden
        Phone: (+46) 8 790 8463                         
        Fax:   (+46) 8 790 7260
        Email: address@hidden
        WWW: http://www.s3.kth.se/~mabe
=============================================