Re: auto beam issue

[Aaron Hill]

On 2022-11-02 4:42 am, Werner LEMBERG wrote:
> While working on the LM I see the following example in section 4.1.3:
>
> ```
> \new Staff {
>   \relative {
>     r4 g'8 g c4 c8 d |
>     e4 r8
>     <<
>       { f8 c c }
>       \new Staff { f8 f c }
>     >>
>     r4 |
>   }
> }
> ```
>
> I now wonder why the last two notes of the temporary (lower) staff
> don't have a beam, similar to the upper staff.  Is this a bug?

This appears to be due to the default beamExceptions for 4/4 time.  
Consider:

%%%%
\new Staff {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c }
      \new Staff { \set Timing.beamExceptions = #'() f8 f c }
    >>
    r4 |
  }
}
%%%%

Note that if you allow both staves to include the rest explicitly, the 
beam appears:

%%%%
\new Staff {
  \relative {
    r4 g'8 g c4 c8 d |
    e4 r8
    <<
      { f8 c c r4 }
      \new Staff { f8 f c r4 }
    >>
  }
}
%%%%


-- Aaron Hill