### 3.1.124 TieColumn

TieColumn objects are created by: Completion_heads_engraver and Tie_engraver.

Standard settings:

> `before-line-breaking` (boolean):

>   `ly:tie-column::before-line-breaking`

>   Dummy property, used to trigger a callback function.

> `X-extent` (pair of numbers)

>   Extent (size) in the X direction, measured in staff-space units, relative to object’s reference point.

> `Y-extent` (pair of numbers)

>   Extent (size) in the Y direction, measured in staff-space units, relative to object’s reference point.

This object supports the following interface(s): grob-interface, spanner-interface and tie-column-interface.

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