Barlines are indicated by a token starting with an equals sign. A optional number can immediately follow the equals sign, representing a measure number. VHV will display the bar number at each system break, excluding a label for measure 1:
Following the measure number can be an optional styling for the barline.
- means an
|| is a double thin barline,
|!: is a left-repeat,
:|!|: is a left-right repeat. A special style is
==, representing a final
barline. This bar usually does not include a bar number, since it is the last
one in the piece/movement.
Humdrum can represent more barline styles, but the above types are currently supported in verovio.
Typically the initial barline should be labeled in the Humdrum
encoding even though it is not printed. Either
be used at the start of the first measure (with
- meaning an
invisible barline), but the starting barline will be automatically
suppressed if it is a regular barline. Labeling the first bar is
necessary if you need to extract it by measure number with a tool
such as myank.
Pickup beats do not have a barline at their start. If a measure
does not match the duration of the time signature at the start of
the music and the data does not start with a barline, it will be
automatically interpreted as a pick-up measure and automatically
assigned 0 as the measure number for use with the
Here is example music with a pick-up beat, and a typical ending that drops the duration of the pickup measure: