Re: printing rest in ChordNames context

[Tim McNamara]

On May 14, 2009, at 1:03 AM, Marc Hohl wrote:

> Tim McNamara schrieb:
> > [...]
> > In jazz lead sheets, the usual method is to write "N.C." above the  
> > staff ("No Chord") which cues the chordal instruments and rhythm  
> > section to stop playing to allow the break.  There's a workaround  
> > that Martial wrote to facilitate this, but it would be nice to  
> > have a way of writing this more simply (e.g., nc+duration such as  
> > nc1, nc2, nc4, nc8 etc.).
> What about writing just r1, r2, r4 as usual, and let lilypond  
> convert this into "N.C."?
> I have no perfect solution, but it should be possible by including  
> the Rest_engraver and defining it
> to simply print the "N.C.".
>
> With this solution, you can use the chords as notes /and/ as text  
> symbols.

That's an interesting possibility that I'd have to look into, since I  
haven't got a clue about using the Rest_engraver, although I suspect  
it would involve putting in a lot of code inside the music content.   
Many things in Lilypond currently result in inelegant coding in  
the .ly file to get the job done, although this will eventually be  
refined.  If I had any computer programming skills I'd be happy to  
help with writing those refinements, but alas I wold first have to go  
back to school and learn computer programming!

Martial's snippet from a couple of days ago is very helpful in  
creating a "N.C." in the chords above the staff and works well:

\version "2.12.2"

NCString  = { <c e g>-\markup { \whiteout { \hspace #-2 " N.C.    " }}}
ChrdExcep = #(append (sequential-music-to-chord-exceptions NCString #t)
           ignatzekExceptions)


{<<
{
\chords {
a2:m7 d2:7.9-
g2:m7 c2:7
\set   chordNameExceptions = #ChrdExcep c1 %chord <c e g> as NCString
\unset chordNameExceptions
a2:m7 d2:7.9-
}
}
\relative c' {
a'2 d2
g,2 c2
c4 c4 c4 c4
a2 r2}
>>
}

but having to put

\set   chordNameExceptions = #ChrdExcep c1 %chord <c e g> as NCString
\unset chordNameExceptions

into the \chords feels clunky and intrusive to me.  I'd prefer to  
minimize putting formatting code in the music content as much as  
possible.  Being able to write something like nc1 (or r1) and have it  
interpreted by LilyPond as N.C. would be much more elegant and  
intuitive:

{<<
{
\chords {
a2:m7 d2:7.9-
g2:m7 c2:7
nc1
a2:m7 d2:7.9-
}
}
\relative c' {
a'2 d2
g,2 c2
c4 c4 c4 c4
a2 r2}
>>
}


IMHO, YMMV.