6.2.5 Bar check

Bar checks help detect errors in the durations. A bar check is entered using the bar symbol, `|'. Whenever it is encountered during interpretation, it should fall on a measure boundary. If it does not, a warning is printed. In the next example, the second bar check will signal an error

\time 3/4 c2 e4 | g2 |

Bar checks can also be used in lyrics, for example

\lyricmode {
  \time 2/4
  Twin -- kle | Twin -- kle
}

Failed bar checks are caused by entering incorrect durations. Incorrect durations often completely garble up the score, especially if the score is polyphonic, so a good place to start correcting input is by scanning for failed bar checks and incorrect durations.

It is also possible to redefine the meaning of |. This is done by assigning a music expression to pipeSymbol,

     
     pipeSymbol = \bar "||"
     
     { c'2 c' | c'2 c' }

Other languages: French.