## 5.3 Large projects

When working on a large project, having a clear structure to your lilypond input files becomes vital.

- Use a variable for each voice, with a minimum of structure inside the definition. The structure of the `\score` section is the most likely thing to change; the `violin` definition is extremely unlikely to change in a new version of LilyPond.

  >     violin = \relative c'' {
  >     g4 c'8. e16
  >     }
  >     …
  >     \score {
  >       \new GrandStaff {
  >         \new Staff {
  >           \violin
  >         }
  >       }
  >     }

- Separate tweaks from music definitions. This point was made previously, but for large projects it is absolutely vital. We might need to change the definition of `fthenp`, but then we only need to do this once, and we can still avoid touching anything inside `violin`.

  >     fthenp = _\markup{
  >       \dynamic f \italic \small { 2nd } \hspace #0.1 \dynamic p }
  >     violin = \relative c'' {
  >     g4\fthenp c'8. e16
  >     }

其他语言：deutsch, español, français, magyar, italiano, 日本語。
About automatic language selection.

#### LilyPond — Usage v2.18.2 (稳定分支).