LilyPond Internals Reference: 2.2.42 Forbid_line_break_engraver

### 2.2.42 Forbid_line_break_engraver

Forbid line breaks when note heads are still playing at some point.

Properties (read)

> `busyGrobs` (list)

>   A queue of `(end-moment . GROB)` cons cells. This is for internal (C++) use only. This property contains the grobs which are still busy (e.g. note heads, spanners, etc.).

Properties (write)

> `forbidBreak` (boolean)

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

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

#### Internals Reference