Re: Possible bug, or I am doing something wrong?

[David Kastrup]

Sami Amiris <address@hidden> writes:

> David Kastrup <dak <at> gnu.org> writes:
>
>> 
>> Sami Amiris <sami.amiris <at> gmail.com> writes:
>> 
>> > Please run this, it is self-explanatory. It is an issue with
>> > autochange and
>> > beaming. Is it me, or a bug?
>> 
>> You are doing something wrong.  You don't start a voice before writing
>> \autochange, and so \autochange _first_ changes the Staff, and then
>> there is no longer a need to start a new implicit voice since the upper
>> staff already _has_ an implicit voice.
>> 
>> So for the lower staff, try writing
>> \new Voice \autochange ...
>> and the autochange voice will get started in the lower staff and remain
>> rooted there.
>> 
>
> I have trimmed it like this:
>
> \version "2.14.2"
> \score
>       {
>       \new PianoStaff
>       <<
>               \new Staff = "up"{
>               \clef treble
>               \new Voice = "upper"
>               \autochange {
>               \relative c'' %If this becomes c' or lower, everything ok.
>                               %as it is, it puts everything in the voice of 
> "down".
>                       {
>                       \stemUp{        
>                       \bar "|:" bes4 c bes' c \bar ":|" d1 \bar "|."
>                       }}}}
>                               
>               \new Staff = "down"{
>               \clef bass
>               \new Voice = "lower"
>               \autochange {
>               \relative c' %this is of no consequence, really
>                       {
>                       \stemDown{      
>                        bes4 c bes' c | d1 
>                       }}}}
>       >>
>       }       
>
> I have put new voices, but it still doesn't work. How would this work?
> I am a relative newbie, so please excuse the clumsiness...

There are so many things going wrong here that it is not actually easy
to start.  This is still not a minimal example, and in fact it would
warrant several minimal examples.

One thing that goes wrong is that \bar complains because it tries
accessing the Timing context before it has even been created.  Starting
music with \bar apparently is not supported.  Acutely embarrassing.

But that does not seem related to the \autochange going haywire: it is
not clear to me whether this is because the material ends up in the same
voice, or whether it is just that one of the \stemUp/\stemDown does not
have an effect where it would be needed.

-- 
David Kastrup