LilyPond Internals Reference: 3.2.148 system-start-delimiter-interface

### 3.2.148 `system-start-delimiter-interface`

The brace, bracket or bar in front of the system. The following values for `style` are recognized:

`bracket`

  A thick bracket, normally used to group similar instruments in a score. Default for `StaffGroup`. `SystemStartBracket` uses this style.

`brace`

  A ‘piano style’ brace normally used for an instrument that uses two staves. The default style for `GrandStaff`. `SystemStartBrace` uses this style.

`bar-line`

  A simple line between the staves in a score. Default for staves enclosed in `<<` and `>>`. `SystemStartBar` uses this style.

`line-bracket`

  A simple square, normally used for subgrouping instruments in a score. `SystemStartSquare` uses this style.

See also ‘`input/regression/system-start-nesting.ly`’.

#### User settable properties:

`collapse-height` (dimension, in staff space)

  Minimum height of system start delimiter. If equal or smaller, the bracket/brace/line is removed.

`style` (symbol)

  This setting determines in what style a grob is typeset. Valid choices depend on the `stencil` callback reading this property.

`thickness` (number)

  For grobs made up of lines, this is the thickness of the line. For slurs and ties, this is the distance between the two arcs of the curve’s outline at its thickest point, not counting the diameter of the virtual “pen” that draws the arcs. This property is expressed as a multiple of the current staff-line thickness (i.e., the visual output is influenced by changes to `Staff.StaffSymbol.thickness`).

This grob interface is used in the following graphical object(s): `SystemStartBar`, `SystemStartBrace`, `SystemStartBracket` and `SystemStartSquare`.

#### LilyPond – Internals Reference v2.24.4 (stable-branch).