textBuffer()

Headless reactive text document: content, cursor, dirty tracking, and undo history.

Signature

function textBuffer(initial = "", opts?: TextBufferOptions): TextBufferResult

Parameters

Parameter	Type	Description
initial	unknown	Initial document text.
opts	TextBufferOptions	Optional maxHistory, per-field equals for text deduping, and name.

TextBufferOptions

Property	Type	Default	Description
maxHistory	number	100	Max undo steps (minimum 2 internally).
equals	(a: string, b: string) => boolean	—	Optional; when set, compares text fields of snapshots. Indices must still match for equality skip.
name	string	"textBuffer"	Debug name prefix for child stores.

Returns

TextBufferResult — content is derived from the undo stack; history stores TextBufferSnapshot values (text + selection). Use history.undo / redo (not raw index hacks) so the caret stays in sync. replaceRange applies a slice edit and caret in one step.

Options / Behavior Details

• Undo snapshots: Each edit pushes { text, start, end }. Moving the caret alone does not push history — only insert, delete, replace, replaceAll, and replaceRange do.
• Undo/redo: history.undo and redo run in a batch so content and cursor updates commit together for subscribers.