### 2.2.29 Double_percent_repeat_engraver

Make double measure repeats.

Music types accepted:

double-percent-event

Properties (read)

> `countPercentRepeats` (boolean)

>   If set, produce counters for percent repeats.

> `measureLength` (moment)

>   Length of one measure in the current time signature.

> `repeatCountVisibility` (procedure)

>   A procedure taking as arguments an integer and context, returning whether the corresponding percent repeat number should be printed when `countPercentRepeats` is set.

Properties (write)

> `forbidBreak` (boolean)

>   If set to `#t`, prevent a line break at this point.

This engraver creates the following layout object(s):

DoublePercentRepeat and DoublePercentRepeatCounter.

`Double_percent_repeat_engraver` is part of the following context(s): CueVoice, DrumVoice, GregorianTranscriptionVoice, KievanVoice, MensuralVoice, PetrucciVoice, TabVoice, VaticanaVoice and Voice.

#### Internals Reference v2.18.2 (稳定分支).