Re: initial grace notes prevent instrumentName &, systemStartBrace/Square

[Mats Bengtsson]

> Good morning LilyPond,
>
> \version "2.13.31" % on Mac OS X
> \paper{ raggedright = ##t }
>
> initialAcciaccatura = \relative c' {
>        \acciaccatura <c e g>8
>        <d fis a>8
> }
>
> initialGrace = \relative c'' {
>         \grace c16
>         c4
> }
>
> initialAppoggiatura = \relative c'' {
>         \appoggiatura c16
>         c4
> }
>
> middleGrace = \relative c'' {
>         c4 \grace c16
>         c4
> }
>
> \markup { initial acciaccatura prevents instrument name and system
> start brace }
> \score {
>    \new StaffGroup = "Guitar"
>    \with {\consists "Instrument_name_engraver"}
>    <<
>      \set StaffGroup.instrumentName = #"Guitar"
>      \set StaffGroup.systemStartDelimiter = #'SystemStartBrace
>      \new Staff {
>             \initialAcciaccatura
>      }
>      \new TabStaff {
>        \initialAcciaccatura
>      }
>    >>
> }
>
> \markup { initial grace note prevents instrument name and system
> start brace }
> \score {
>    \new StaffGroup = "Guitar"
>    \with {\consists "Instrument_name_engraver"}
>    <<
>      \set StaffGroup.instrumentName = #"Guitar"
>      \set StaffGroup.systemStartDelimiter = #'SystemStartBrace
>      \new Staff {
>             \initialGrace
>      }
>      \new TabStaff {
>        \initialGrace
>      }
>    >>
> }
>
> \markup { initial appoggiatura prevents instrument name and system
> start brace }
> \score {
>    \new StaffGroup = "Guitar"
>    \with {\consists "Instrument_name_engraver"}
>    <<
>      \set StaffGroup.instrumentName = #"Guitar"
>      \set StaffGroup.systemStartDelimiter = #'SystemStartBrace
>      \new Staff {
>             \initialAppoggiatura
>      }
>      \new TabStaff {
>        \initialAppoggiatura
>      }
>    >>
> }
>
> \markup { initial appoggiatura prevents instrument name and system
> start square }
> \score {
>    \new StaffGroup = "Guitar"
>    \with {\consists "Instrument_name_engraver"}
>    <<
>      \set StaffGroup.instrumentName = #"Guitar"
>      \set StaffGroup.systemStartDelimiter = #'SystemStartSquare
>      \new Staff {
>             \initialAppoggiatura
>      }
>      \new TabStaff {
>        \initialAppoggiatura
>      }
>    >>
> }
>
> \markup { grace note after the first note: everything is ok }
> \score {
>    \new StaffGroup = "Guitar"
>    \with {\consists "Instrument_name_engraver"}
>    <<
>      \set StaffGroup.instrumentName = #"Guitar"
>      \set StaffGroup.systemStartDelimiter = #'SystemStartBrace
>      \new Staff {
>             \middleGrace
>      }
>      \new TabStaff {
>        \middleGrace
>      }
>    >>
> }
>
> HTH
> Bug's Bunny
This is just another manifestation of our old favourite bug which is 
documented under "Known issues and warnings" in 
http://lilypond.org/doc/v2.13/Documentation/notation/special-rhythmic-concerns#grace-notes.
However, your example is a bit more subtle, since you do property 
settings that happen in parallel with the grace notes and it seems that 
LilyPond thinks that these settings happen
after the grace notes, which means that they have not taken effect when 
the StaffGroup is created.
There are two simple remedies:
1) Move the settings to the \with{...} clause:
\score {
  \new StaffGroup = "Guitar"
  \with {
    \consists "Instrument_name_engraver"
    instrumentName = #"Guitar"
    systemStartDelimiter = #'SystemStartBrace
  }
  <<
    \new Staff {
           \initialAcciaccatura
    }
    \new TabStaff {
      \initialAcciaccatura
    }
  >>
}


2) Move the settings to within one of the Staff contexts that you define 
and do them before the grace notes:
\score {
  \new StaffGroup = "Guitar"
  \with {\consists "Instrument_name_engraver"}
  <<
         \new Staff {
           \set StaffGroup.instrumentName = #"Guitar"
           \set StaffGroup.systemStartDelimiter = #'SystemStartBrace
           \initialGrace
    }
    \new TabStaff {
      \initialGrace
    }
  >>
}

Of course, alternative 1) is gives a more aesthetically pleasing input file.

    /Mats