### 2.2.118 System_start_delimiter_engraver

Create a system start delimiter (i.e., a `SystemStartBar`, `SystemStartBrace`, `SystemStartBracket` or `SystemStartSquare` spanner).

Properties (read)

> `currentCommandColumn` (graphical (layout) object)

>   Grob that is X-parent to all current breakable (clef, key signature, etc.) items.

> `systemStartDelimiter` (symbol)

>   Which grob to make for the start of the system/staff? Set to `SystemStartBrace`, `SystemStartBracket` or `SystemStartBar`.

> `systemStartDelimiterHierarchy` (pair)

>   A nested list, indicating the nesting of a start delimiters.

This engraver creates the following layout object(s):

SystemStartBar, SystemStartBrace, SystemStartBracket and SystemStartSquare.

`System_start_delimiter_engraver` is part of the following context(s): ChoirStaff, GrandStaff, PianoStaff, Score and StaffGroup.

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