[Lilypond-auto] Issue 2917 in lilypond: Extend \keepWithTag to allow multiple tags

[lilypond]

Status: Accepted
Owner: ----
Labels: Type-Enhancement

New issue 2917 by address@hidden: Extend \keepWithTag to allow multiple  
tags
http://code.google.com/p/lilypond/issues/detail?id=2917

From user Wim van Dommelen:

There is one thing which might interest you even more and that is a scheme  
script produced by Nicolas Sceaux, some years ago (archive: 27 jan 2007  
(http://lists.gnu.org/archive/html/lilypond-user/2007-01/msg00635.html)). I  
use this a lot myself.

He created a routine called \keepWithTags (note the last 's') with which  
you can keep multiple tags in one run. Ideal for even more. I for example  
use the tags 'score' and 'part' for what I showed below, but also 'cello'  
or 'clarinet' when transposing instruments, you can e.g. think on:

% first voice:
music = \relative c' {
  \tag #'cello \clef bass
  \tag #'clarinet \clef treble
  b4-\tag #'score -\tag #'part ^\markup { \bold "Allegro" }
  g' d d,
}

and quote this with

\keepWithTags #'(clarinet score) \transpose bes, c' { \music }

for the first voice, the second voice would only have the markup for the  
part when printed seperatedly but quoted from a musical string but with  
#'(clarinet part). When ready you don't have to change any bit anymore to  
print score, part, different instruments, etc.

Actually I would propose to add this function (for including multiple tags)  
as a standard feature in LilyPond.