Extensions API

The Extensions API provides built-in extensions and helper functions for creating extension sets.

Built-in Extensions

All built-in extensions implement the Extension interface and can be used directly or customized with options.

TextExtension

Provides text input functionality (insert, delete, replace).

Location: packages/extensions/src/text.ts

Options:

interface TextExtensionOptions {
  enabled?: boolean;  // Whether extension is enabled (default: true)
}

Commands:

• replaceText - Replaces text in selection range

Example:

import { TextExtension } from '@barocss/extensions';

const extension = new TextExtension({ enabled: true });
editor.use(extension);

DeleteExtension

Provides delete functionality (Backspace, Delete keys).

Location: packages/extensions/src/delete.ts

Options:

interface DeleteExtensionOptions {
  enabled?: boolean;
}

Commands:

• deleteSelection - Deletes selected content
• deleteBackward - Deletes backward
• deleteForward - Deletes forward

Example:

import { DeleteExtension } from '@barocss/extensions';

const extension = new DeleteExtension();
editor.use(extension);

BoldExtension

Provides bold formatting functionality.

Location: packages/extensions/src/bold.ts

Options:

interface BoldExtensionOptions {
  enabled?: boolean;
  keyboardShortcut?: string;  // Default: 'Mod+b'
}

Commands:

• toggleBold - Toggles bold formatting

Keybindings:

• Mod+b - Toggle bold (default)

Example:

import { BoldExtension, createBoldExtension } from '@barocss/extensions';

// Direct instantiation
const extension = new BoldExtension({ keyboardShortcut: 'Mod+b' });

// Or use convenience function
const extension = createBoldExtension({ keyboardShortcut: 'Mod+b' });

editor.use(extension);

ItalicExtension

Provides italic formatting functionality.

Location: packages/extensions/src/italic.ts

Options:

interface ItalicExtensionOptions {
  enabled?: boolean;
  keyboardShortcut?: string;  // Default: 'Mod+i'
}

Commands:

• toggleItalic - Toggles italic formatting

Keybindings:

• Mod+i - Toggle italic (default)

Example:

import { ItalicExtension, createItalicExtension } from '@barocss/extensions';

const extension = createItalicExtension();
editor.use(extension);

UnderlineExtension

Provides underline formatting functionality. Supports cross-node selections.

Location: packages/extensions/src/underline.ts

Commands:

• toggleUnderline - Toggles underline formatting (works across multiple nodes)

Example:

import { UnderlineExtension } from '@barocss/extensions';

const extension = new UnderlineExtension();
editor.use(extension);

StrikethroughExtension

Provides strikethrough formatting functionality. Supports cross-node selections.

Location: packages/extensions/src/strikethrough.ts

Commands:

• toggleStrikethrough - Toggles strikethrough formatting (works across multiple nodes)

Example:

import { StrikethroughExtension } from '@barocss/extensions';

const extension = new StrikethroughExtension();
editor.use(extension);

HeadingExtension

Provides heading functionality. The removeHeading command correctly transforms a heading back to a paragraph using transformNode within a transaction (supports undo/redo).

Location: packages/extensions/src/heading.ts

Options:

interface HeadingExtensionOptions {
  enabled?: boolean;
  levels?: number[];  // Supported heading levels (default: [1, 2, 3, 4, 5, 6])
}

Commands:

• setHeading - Sets heading level
• removeHeading - Converts heading to paragraph (via transformNode('paragraph'))
• toggleHeading - Toggles heading on/off

Keybindings:

• Mod+Alt+1 - Set heading level 1
• Mod+Alt+2 - Set heading level 2
• Mod+Alt+3 - Set heading level 3
• Mod+Alt+4 - Set heading level 4
• Mod+Alt+5 - Set heading level 5
• Mod+Alt+6 - Set heading level 6

Example:

import { HeadingExtension, createHeadingExtension } from '@barocss/extensions';

const extension = createHeadingExtension({ levels: [1, 2, 3] });
editor.use(extension);

ListExtension

Provides bullet list and ordered list functionality.

Location: packages/extensions/src/list.ts

Commands:

• toggleBulletList - Toggles unordered (bullet) list
• toggleOrderedList - Toggles ordered (numbered) list
• splitListItem - Splits list item at cursor (Enter key behavior in lists)

Example:

import { ListExtension } from '@barocss/extensions';

const extension = new ListExtension();
editor.use(extension);

BlockquoteExtension

Provides blockquote functionality.

Location: packages/extensions/src/blockquote.ts

Commands:

• toggleBlockquote - Toggles blockquote on/off

Example:

import { BlockquoteExtension } from '@barocss/extensions';

const extension = new BlockquoteExtension();
editor.use(extension);

ParagraphExtension

Provides paragraph functionality.

Location: packages/extensions/src/paragraph.ts

Commands:

• insertParagraph - Inserts a new paragraph
• setParagraph - Sets paragraph type

Example:

import { ParagraphExtension } from '@barocss/extensions';

const extension = new ParagraphExtension();
editor.use(extension);

IndentExtension

Provides indentation functionality.

Location: packages/extensions/src/indent.ts

Options:

interface IndentExtensionOptions {
  enabled?: boolean;
}

Commands:

• indent - Indents block
• outdent - Outdents block

Keybindings:

• Tab - Indent
• Shift+Tab - Outdent

Example:

import { IndentExtension } from '@barocss/extensions';

const extension = new IndentExtension();
editor.use(extension);

MoveSelectionExtension

Provides selection movement functionality.

Location: packages/extensions/src/move-selection.ts

Commands:

• moveSelectionUp - Moves selection up
• moveSelectionDown - Moves selection down
• moveSelectionLeft - Moves selection left
• moveSelectionRight - Moves selection right

Keybindings:

• ArrowUp - Move selection up
• ArrowDown - Move selection down
• ArrowLeft - Move selection left
• ArrowRight - Move selection right

Example:

import { MoveSelectionExtension } from '@barocss/extensions';

const extension = new MoveSelectionExtension();
editor.use(extension);

MoveBlockExtension

Provides block movement functionality.

Location: packages/extensions/src/move-block.ts

Options:

interface MoveBlockExtensionOptions {
  enabled?: boolean;
}

Commands:

• moveBlockUp - Moves block up
• moveBlockDown - Moves block down

Keybindings:

• Mod+ArrowUp - Move block up
• Mod+ArrowDown - Move block down

Example:

import { MoveBlockExtension, createMoveBlockExtension } from '@barocss/extensions';

const extension = createMoveBlockExtension();
editor.use(extension);

SelectAllExtension

Provides select all functionality.

Location: packages/extensions/src/select-all.ts

Commands:

• selectAll - Selects all content

Keybindings:

• Mod+a - Select all

Example:

import { SelectAllExtension } from '@barocss/extensions';

const extension = new SelectAllExtension();
editor.use(extension);

CopyPasteExtension

Provides clipboard functionality.

Location: packages/extensions/src/copy-paste.ts

Commands:

• copy - Copies selected content
• cut - Cuts selected content
• paste - Pastes content at selection

Keybindings:

• Mod+c - Copy
• Mod+x - Cut
• Mod+v - Paste

Example:

import { CopyPasteExtension } from '@barocss/extensions';

const extension = new CopyPasteExtension();
editor.use(extension);

EscapeExtension

Provides escape functionality.

Location: packages/extensions/src/escape.ts

Commands:

• escape - Handles escape key

Keybindings:

• Escape - Escape

Example:

import { EscapeExtension } from '@barocss/extensions';

const extension = new EscapeExtension();
editor.use(extension);

---

Extension Factory Functions

createCoreExtensions(): Extension[]

Creates core extensions (required extensions that are always included by default).

Returns:

• Extension[] - Array of core extensions

Includes:

• TextExtension - Basic text editing
• DeleteExtension - Delete command
• ParagraphExtension - Basic structure
• MoveSelectionExtension - Selection movement
• SelectAllExtension - Select all
• IndentExtension - Structural indentation
• CopyPasteExtension - Clipboard operations
• HardBreakExtension - Line break (Shift+Enter)

Note: Core extensions are automatically registered in Editor constructor, so they are excluded from other extension sets.

Example:

import { createCoreExtensions } from '@barocss/extensions';

const coreExtensions = createCoreExtensions();
// Use if you want to manually manage core extensions

createBasicExtensions(): Extension[]

Creates basic extensions (formatting extensions).

Returns:

• Extension[] - Array of basic extensions

Includes:

• BoldExtension - Bold formatting
• ItalicExtension - Italic formatting
• HeadingExtension - Heading support
• ListExtension - Bullet/ordered list support
• BlockquoteExtension - Blockquote support

Note: Core extensions are automatically registered, so they are excluded.

Example:

import { createBasicExtensions } from '@barocss/extensions';

const basicExtensions = createBasicExtensions();
editor.use(...basicExtensions);

ExtensionSets

Predefined extension sets for common use cases.

Location: packages/extensions/src/index.ts

ExtensionSets.basic()

Basic text editing extensions (Bold, Italic, Underline only).

Returns:

• Extension[] - Array of extensions

Includes:

• BoldExtension
• ItalicExtension
• UnderlineExtension

Example:

import { ExtensionSets } from '@barocss/extensions';

const extensions = ExtensionSets.basic();
editor.use(...extensions);

ExtensionSets.rich()

Full rich text editing extensions (all formatting, rich content, marks, document structure).

Returns:

• Extension[] - Array of extensions

Includes all createRichExtensions() — see the full list above.

Example:

import { ExtensionSets } from '@barocss/extensions';

const extensions = ExtensionSets.rich();
editor.use(...extensions);

ExtensionSets.minimal()

Minimal extensions (no additional extensions).

Returns:

• Extension[] - Empty array

Example:

import { ExtensionSets } from '@barocss/extensions';

const extensions = ExtensionSets.minimal();
// Returns: []

---

Convenience Functions

createBoldExtension(options?: BoldExtensionOptions): BoldExtension

Creates a BoldExtension instance.

Parameters:

• options?: BoldExtensionOptions - Optional options

Returns:

• BoldExtension - BoldExtension instance

Example:

import { createBoldExtension } from '@barocss/extensions';

const extension = createBoldExtension({ keyboardShortcut: 'Mod+b' });
editor.use(extension);

createItalicExtension(options?: ItalicExtensionOptions): ItalicExtension

Creates an ItalicExtension instance.

Parameters:

• options?: ItalicExtensionOptions - Optional options

Returns:

• ItalicExtension - ItalicExtension instance

createHeadingExtension(options?: HeadingExtensionOptions): HeadingExtension

Creates a HeadingExtension instance.

Parameters:

• options?: HeadingExtensionOptions - Optional options

Returns:

• HeadingExtension - HeadingExtension instance

createMoveBlockExtension(options?: MoveBlockExtensionOptions): MoveBlockExtension

Creates a MoveBlockExtension instance.

Parameters:

• options?: MoveBlockExtensionOptions - Optional options

Returns:

• MoveBlockExtension - MoveBlockExtension instance

---

Complete Examples

Example 1: Using Core Extensions Only

import { Editor } from '@barocss/editor-core';
// Core extensions are automatically registered
const editor = new Editor();

Example 2: Adding Basic Extensions

import { Editor } from '@barocss/editor-core';
import { createBasicExtensions } from '@barocss/extensions';

const editor = new Editor({
  extensions: createBasicExtensions()
});

Example 3: Using Extension Sets

import { Editor } from '@barocss/editor-core';
import { ExtensionSets } from '@barocss/extensions';

const editor = new Editor({
  extensions: ExtensionSets.rich()
});

Example 4: Custom Extension Combination

import { Editor } from '@barocss/editor-core';
import { 
  BoldExtension, 
  ItalicExtension, 
  HeadingExtension,
  UnderlineExtension,
  StrikethroughExtension
} from '@barocss/extensions';

const editor = new Editor({
  extensions: [
    new BoldExtension(),
    new ItalicExtension(),
    new HeadingExtension({ levels: [1, 2, 3] }),
    new UnderlineExtension(),
    new StrikethroughExtension()
  ]
});

Example 5: Customizing Extension Options

import { Editor } from '@barocss/editor-core';
import { 
  BoldExtension, 
  ItalicExtension,
  HeadingExtension
} from '@barocss/extensions';

const editor = new Editor({
  extensions: [
    new BoldExtension({ 
      enabled: true,
      keyboardShortcut: 'Mod+Shift+b'  // Custom shortcut
    }),
    new ItalicExtension({
      enabled: true,
      keyboardShortcut: 'Mod+Shift+i'
    }),
    new HeadingExtension({
      enabled: true,
      levels: [1, 2, 3]  // Only support h1, h2, h3
    })
  ]
});

---

Rich Content Extensions

LinkExtension

Provides link insertion and editing functionality.

Commands: insertLink, removeLink

ImageExtension

Provides image insertion functionality.

Commands: insertImage

CodeBlockExtension

Provides code block functionality.

Commands: insertCodeBlock, toggleCodeBlock

HorizontalRuleExtension

Provides horizontal rule insertion.

Commands: insertHorizontalRule

TableExtension

Provides table creation and editing (bTable, bTableRow, bTableCell, etc.).

Commands: insertTable

CalloutExtension

Provides callout/admonition blocks (info, warning, error, success, note, tip).

Commands: insertCallout

ChecklistExtension

Provides checklist/task list functionality. Uses transactions for undo/redo support.

Commands: insertChecklist, toggleChecklistItem

MathBlockExtension

Provides math equation blocks (KaTeX).

Commands: insertMathBlock

CommentExtension

Provides comment/annotation functionality (commentThread).

Commands: insertComment

HardBreakExtension

Provides line break within a block (Shift+Enter).

Commands: insertHardBreak

PageBreakExtension

Provides page break insertion (atom block).

Commands: insertPageBreak

MathInlineExtension

Provides inline math equation insertion (KaTeX).

Commands: insertMathInline — payload: { tex?: string }

PullQuoteExtension

Provides pull quote blocks (distinct from blockquote).

Commands: insertPullQuote — payload: { text?: string }

ColumnsExtension

Provides multi-column layout (columns/column nodes).

Commands:

• insertColumns — payload: { count?: number } (default: 2)
• addColumn — payload: { columnsId: string }
• removeColumn — payload: { columnsId: string, columnId: string }

TocExtension

Provides table of contents insertion (atom block).

Commands: insertToc

DetailsExtension

Provides collapsible content blocks (bDetails/bSummary).

Commands: insertDetails — payload: { summary?: string }

DescriptionListExtension

Provides description list blocks (descList/descTerm/descDef).

Commands:

• insertDescriptionList
• addDescriptionItem — payload: { descListId: string }

FigureExtension

Provides figure with caption (bFigure/bFigcaption).

Commands:

• insertFigure — payload: { src?: string, alt?: string, caption?: string }
• setFigcaption — payload: { figureId: string, caption?: string }

MediaExtension

Provides video, audio, and embed insertion.

Commands:

• insertVideo — payload: { src: string, poster?: string }
• insertAudio — payload: { src: string }
• insertEmbed — payload: { provider: string, id: string, title?: string }

Mark Extensions

CodeMarkExtension

Provides inline code mark (Ctrl+E).

Commands: toggleCode

HighlightExtension

Provides text highlight mark with configurable color.

Commands: toggleHighlight — payload: { color?: string } (default: #ffeb3b)

FontColorExtension

Provides text color and background color marks.

Commands:

• setFontColor — payload: { color: string }
• removeFontColor
• setBgColor — payload: { color: string }
• removeBgColor

SubSuperExtension

Provides subscript and superscript marks.

Commands: toggleSubscript, toggleSuperscript

FontSizeExtension

Provides font size mark.

Commands:

• setFontSize — payload: { size: string } (e.g. '18px')
• removeFontSize

FontFamilyExtension

Provides font family mark.

Commands:

• setFontFamily — payload: { family: string } (e.g. 'Georgia')
• removeFontFamily

TextFormattingExtension

Aggregates less-common text-style marks into one extension.

Toggle commands (no additional payload needed):

• toggleSmallCaps — smallCaps mark
• toggleKbd — kbd mark (keyboard key)
• toggleSpoiler — spoiler mark

Apply commands (require value in payload):

• setLetterSpacing — letterSpacing mark ({ value: '0.2em' })
• setWordSpacing — wordSpacing mark
• setLineHeight — lineHeight mark
• setTextShadow — textShadow mark

Multi-attr commands (require attrs in payload):

• setBorder — border mark ({ attrs: { style, width, color } })
• setSpanLang — spanLang mark ({ attrs: { lang, dir } })

MentionExtension

Provides @mention mark.

Commands: insertMention — payload: { id: string }

FootnoteExtension

Provides footnote definition (footnoteDef) and reference (footnoteRef mark).

Commands:

• insertFootnote — payload: { id: string, text?: string } (creates both def + ref)
• insertFootnoteRef — payload: { id: string } (ref only)

Inline Atom Extensions

BookmarkExtension

Provides bookmark anchor insertion.

Commands: insertBookmark — payload: { id: string }

FieldExtension

Provides document field insertions (page number, date, title, etc.).

Commands:

• insertFieldPageNumber
• insertFieldPageCount
• insertFieldDateTime — payload: { format?: string }
• insertFieldDocTitle
• insertFieldAuthor

Document Structure Extension

DocStructureExtension

Aggregates document-level structural blocks.

Commands:

• insertDocSection — document section
• insertDocHeader — document header
• insertDocFooter — document footer
• insertBibliography — bibliography block
• insertEndnote — payload: { attrs: { id: string } }
• insertIndexBlock — index block
• insertChart — payload: { attrs: { title?: string, values: string } }

UX Extensions

SlashCommandExtension

Provides slash command menu (type / to see command palette).

FloatingToolbarExtension

Provides floating toolbar that appears on text selection.

DragDropExtension

Provides block-level drag and drop with auto-scroll and ESC cancellation.

Commands: moveBlockToPosition

FindReplaceExtension

Provides find and replace functionality.

Commands: find, findAndReplace

Keybindings: Mod+f (find), Mod+h (find and replace)

---

createRichExtensions(): Extension[]

Creates all rich content extensions (includes basic + all schema-complete extensions).

Returns: Extension[]

Includes all of createBasicExtensions() plus:

Category	Extensions
Formatting	Underline, StrikeThrough, CodeMark, Highlight, FontColor, SubSuper, FontSize, FontFamily, TextFormatting
Rich Content	Link, Image, CodeBlock, HorizontalRule, Table, Checklist, Callout, MathBlock, MathInline, Comment, PageBreak
Block Structures	PullQuote, Columns, Toc, Details, DescriptionList, Figure
Media	Media (Video, Audio, Embed)
Inline Atoms	Mention, Footnote, Bookmark, Field
Document	DocStructure
Editing	MoveBlock, DragDrop

Example:

import { createRichExtensions } from '@barocss/extensions';

const richExtensions = createRichExtensions();
editor.use(...richExtensions);

Extension Options Summary

Core Extensions (always included)

Extension	Keybindings	Commands
TextExtension	-	replaceText
DeleteExtension	-	deleteSelection, deleteBackward, deleteForward
ParagraphExtension	-	insertParagraph, setParagraph
MoveSelectionExtension	Arrow keys, Shift+Arrow	moveSelection*, extendSelection*
SelectAllExtension	Mod+a	selectAll
IndentExtension	Tab, Shift+Tab	indent, outdent
CopyPasteExtension	Mod+c/x/v	copy, cut, paste
EscapeExtension	Escape	escape
HardBreakExtension	-	insertHardBreak

Basic Extensions

Extension	Keybindings	Commands
BoldExtension	Mod+b	toggleBold
ItalicExtension	Mod+i	toggleItalic
HeadingExtension	Mod+Alt+1-6	setHeading1-6, setHeading, removeHeading
ListExtension	-	toggleBulletList, toggleOrderedList, splitListItem
BlockquoteExtension	-	toggleBlockquote

Rich Extensions — Formatting Marks

Extension	Commands
UnderlineExtension	toggleUnderline
StrikeThroughExtension	toggleStrikeThrough
CodeMarkExtension	toggleCode
HighlightExtension	toggleHighlight
FontColorExtension	setFontColor, removeFontColor, setBgColor, removeBgColor
SubSuperExtension	toggleSubscript, toggleSuperscript
FontSizeExtension	setFontSize, removeFontSize
FontFamilyExtension	setFontFamily, removeFontFamily
TextFormattingExtension	toggleSmallCaps, toggleKbd, toggleSpoiler, setLetterSpacing, setWordSpacing, setLineHeight, setTextShadow, setBorder, setSpanLang
MentionExtension	insertMention
FootnoteExtension	insertFootnote, insertFootnoteRef

Rich Extensions — Block Content

Extension	Commands
LinkExtension	insertLink, removeLink
ImageExtension	insertImage
CodeBlockExtension	insertCodeBlock, toggleCodeBlock
HorizontalRuleExtension	insertHorizontalRule
PageBreakExtension	insertPageBreak
TableExtension	insertTable
ChecklistExtension	insertChecklist, toggleChecklistItem
CalloutExtension	insertCallout
MathBlockExtension	insertMathBlock
MathInlineExtension	insertMathInline
CommentExtension	insertComment
PullQuoteExtension	insertPullQuote
ColumnsExtension	insertColumns, addColumn, removeColumn
TocExtension	insertToc
DetailsExtension	insertDetails
DescriptionListExtension	insertDescriptionList, addDescriptionItem
FigureExtension	insertFigure, setFigcaption
MediaExtension	insertVideo, insertAudio, insertEmbed
BookmarkExtension	insertBookmark
FieldExtension	insertFieldPageNumber, insertFieldPageCount, insertFieldDateTime, insertFieldDocTitle, insertFieldAuthor
DocStructureExtension	insertDocSection, insertDocHeader, insertDocFooter, insertBibliography, insertEndnote, insertIndexBlock, insertChart

UX Extensions

Extension	Keybindings	Commands
MoveBlockExtension	Mod+ArrowUp/Down	moveBlockUp, moveBlockDown
DragDropExtension	-	moveBlockToPosition
FindReplaceExtension	Mod+f, Mod+h	find, findAndReplace
SlashCommandExtension	/	-
FloatingToolbarExtension	-	-

---

Schema Coverage

All 48 node types and 24 marks in the standard schema have corresponding extensions:

Nodes:  48/48 covered (100%)
Marks:  24/24 covered (100%)
Total commands: 90+

---

Related

• Extension Design Guide - Creating custom extensions
• Advanced Extension Patterns - Advanced extension patterns
• Editor Core API - Extension interface and lifecycle
• Model Operations API - Using operations in extensions