3.3.2 Different editions from one source

Several mechanisms are available to facilitate the generation of different versions of a score from the same music source. Variables are perhaps most useful for combining lengthy sections of music and/or annotation in various ways, while tags are more useful for selecting one from several alternative shorter sections of music. Whichever method is used, separating the notation from the structure of the score will make it easier to change the structure while leaving the notation untouched.


Using variables

If sections of the music are defined in variables they can be reused in different parts of the score, see pieces with variables Organizing pieces with variables. For example, an a cappella vocal score frequently includes a piano reduction of the parts for rehearsal purposes which is identical to the vocal music, so the music need be entered only once. Music from two variables may be combined on one staff, see Automatic part combining. Here is an example:

sopranoMusic = \relative c'' { a4 b c b8( a)}
altoMusic = \relative g' { e4 e e f }
tenorMusic = \relative c' { c4 b e d8( c) }
bassMusic = \relative c' { a4 gis a d, }
allLyrics = \lyricmode {King of glo -- ry }
<<
  \new Staff = "Soprano" \sopranoMusic
  \new Lyrics \allLyrics
  \new Staff = "Alto" \altoMusic
  \new Lyrics \allLyrics
  \new Staff = "Tenor" {
    \clef "treble_8"
    \tenorMusic
  }
  \new Lyrics \allLyrics
  \new Staff = "Bass" {
    \clef "bass"
    \bassMusic
  }
  \new Lyrics \allLyrics
  \new PianoStaff <<
    \new Staff = "RH" {
      \set Staff.printPartCombineTexts = ##f
      \partcombine
      \sopranoMusic
      \altoMusic
    }
    \new Staff = "LH" {
      \set Staff.printPartCombineTexts = ##f
      \clef "bass"
      \partcombine
      \tenorMusic
      \bassMusic
    }
  >>
>>

[image of music]

Separate scores showing just the vocal parts or just the piano part can be produced by changing just the structural statements, leaving the musical notation unchanged.

For lengthy scores, the variable definitions may be placed in separate files which are then included, see Including LilyPond files.


Using tags

The \tag #'partA command marks a music expression with the name partA. Expressions tagged in this way can be selected or filtered out by name later, using either \keepWithTag #'name or \removeWithTag #'name. The result of applying these filters to tagged music is as follows:

Filter

Result

Tagged music preceded by \keepWithTag #'name

Untagged music and music tagged with name is included; music tagged with any other tag name is excluded.

Tagged music preceded by \removeWithTag #'name

Untagged music and music tagged with any tag name other than name is included; music tagged with name is excluded.

Tagged music not preceded by either \keepWithTag or \removeWithTag

All tagged and untagged music is included.

The arguments of the \tag, \keepWithTag and \removeWithTag commands should be a symbol (such as #'score or #'part), followed by a music expression.

In the following example, we see two versions of a piece of music, one showing trills with the usual notation, and one with trills explicitly expanded:

music = \relative g' {
  g8. c32 d
  \tag #'trills {d8.\trill }
  \tag #'expand {\repeat unfold 3 {e32 d} }
  c32 d
 }

\score {
  \keepWithTag #'trills \music
}
\score {
  \keepWithTag #'expand \music
}

[image of music]

Alternatively, it is sometimes easier to exclude sections of music:

music = \relative g' {
  g8. c32 d
  \tag #'trills {d8.\trill }
  \tag #'expand {\repeat unfold 3 {e32 d} }
  c32 d
 }

\score {
  \removeWithTag #'expand
  \music
}
\score {
  \removeWithTag #'trills
  \music
}

[image of music]

Tagged filtering can be applied to articulations, texts, etc. by prepending

-\tag #'your-tag

to an articulation. For example, this would define a note with a conditional fingering indication and a note with a conditional annotation:

c1-\tag #'finger ^4
c1-\tag #'warn ^"Watch!"

Multiple tags may be placed on expressions with multiple \tag entries:

music = \relative c'' {
  \tag #'a \tag #'both { a a a a }
  \tag #'b \tag #'both { b b b b }
}
<<
\keepWithTag #'a \music
\keepWithTag #'b \music
\keepWithTag #'both \music
>>

[image of music]

Multiple \removeWithTag filters may be applied to a single music expression to remove several differently named tagged sections:

music = \relative c'' {
\tag #'A { a a a a }
\tag #'B { b b b b }
\tag #'C { c c c c }
\tag #'D { d d d d }
}
{
\removeWithTag #'B
\removeWithTag #'C
\music
}

[image of music]

Two or more \keepWithTag filters applied to a single music expression will cause all tagged sections to be removed, as the first filter will remove all tagged sections except the one named, and the second filter will remove even that tagged section.

See also

Learning Manual: Organizing pieces with variables.

Notation Reference: Automatic part combining, Including LilyPond files.


Other languages: espaƱol, deutsch.

Notation Reference