### 3.2.61 line-spanner-interface

Generic line drawn between two objects, e.g., for use with glissandi.

#### User settable properties:

> `bound-details` (list)

>   An alist of properties for determining attachments of spanners to edges.

> `extra-dy` (number)

>   Slope glissandi this much extra.

> `gap` (dimension, in staff space)

>   Size of a gap in a variable symbol.

> `left-bound-info` (list)

>   An alist of properties for determining attachments of spanners to edges.

> `right-bound-info` (list)

>   An alist of properties for determining attachments of spanners to edges.

> `simple-Y` (boolean)

>   Should the Y placement of a spanner disregard changes in system heights?

> `thickness` (number)

>   Line thickness, generally measured in `line-thickness`.

> `to-barline` (boolean)

>   If true, the spanner will stop at the bar line just before it would otherwise stop.

#### Internal properties:

> `note-columns` (array of grobs)

>   An array of `NoteColumn` grobs.

This grob interface is used in the following graphical object(s): DynamicTextSpanner, Episema, Glissando, TextSpanner, TrillSpanner and VoiceFollower.

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