Plugin Input Rules

Plugin Input Rules are Plate's runtime for typed editor conversions. As you type, paste, or press Enter, Plate walks the rules registered for that input and lets the first matching rule transform the editor on the spot — a markdown prefix becomes a heading, a fence becomes a code block, a URL becomes a link, -> becomes →.

Not to be confused with Plugin Rules, which control node behavior policy (what Enter and Backspace do inside a block). This page is about what happens when you type a pattern.

This guide walks you through turning on the shipped markdown rules, adding local text substitutions, authoring custom rules, and — at the end — the exact helper reference.

What Plugin Input Rules Are

When you type a character, press Enter, or paste data, Plate asks every registered input rule "does this fire?" before running the default transform. Each rule declares a target (insertText, insertBreak, or insertData), an optional enabled gate, a resolve function that looks at the current selection and returns a match payload, and an apply function that performs the transform. The first rule whose resolve returns a non-undefined payload gets to run; if nothing matches, the default transform runs as usual.

Ownership splits cleanly into three lanes:

• Core. Owns dispatch, selection helpers, and the low-level authoring surfaces: createMarkInputRule, createBlockStartInputRule, createBlockFenceInputRule, createTextSubstitutionInputRule, createRuleFactory, and defineInputRule.
• Feature packages. Own semantic rule families like HeadingRules, BlockquoteRules, CodeBlockRules, BulletedListRules, MathRules, LinkRules. Each family exports factory functions that return concrete rule instances.
• Kits and apps. Own activation. Nothing is turned on just because a plugin exists — you pass rule instances to inputRules: [...] when you configure a plugin.

Quick Start

Input rules ship as concrete instances you pass into a plugin's inputRules array. The two fastest setup paths are:

1. Drop in feature kits that register feature-owned markdown rules — headings, marks, code blocks, lists, math, links.
2. Drop in a local AutoformatKit to get common text substitutions like -> → → or (c) → ©.

You can use one, both, or neither.

Add Feature-Owned Markdown Rules

Use the same kits you already use for nodes and marks. Each kit registers its own markdown rules on the right plugins, so you don't wire anything by hand:

import { createPlateEditor } from 'platejs/react';
 
import { BasicBlocksKit } from '@/components/editor/plugins/basic-blocks-kit';
import { BasicMarksKit } from '@/components/editor/plugins/basic-marks-kit';
import { CodeBlockKit } from '@/components/editor/plugins/code-block-kit';
import { LinkKit } from '@/components/editor/plugins/link-kit';
import { ListKit } from '@/components/editor/plugins/list-kit';
import { MathKit } from '@/components/editor/plugins/math-kit';
 
const editor = createPlateEditor({
  plugins: [
    ...BasicBlocksKit,
    ...BasicMarksKit,
    ...CodeBlockKit,
    ...ListKit,
    ...LinkKit,
    ...MathKit,
  ],
});Copy

Typing # creates an H1, **bold** turns on the bold mark, a triple-backtick fence creates a code block, - starts a bulleted list, [label](url) creates a link, and so on. Each kit owns its rule wiring — the kit source shows exactly which rules it registers and on which plugins.

Add Local Text Substitutions

AutoformatKit is a small plugin that lives in your app and uses createTextSubstitutionInputRule under the hood. It is not a published package — you own the code and can edit the patterns.

import { createPlateEditor } from 'platejs/react';
 
import { AutoformatKit } from '@/components/editor/plugins/autoformat-kit';
 
const editor = createPlateEditor({
  plugins: [
    // ...otherPlugins,
    ...AutoformatKit,
  ],
});Copy

Type -> and get →. Type (c) and get ©. The full pattern list is visible in the kit source — change it however you like.

Kits are the quick path. If you'd rather wire rules by hand — pick which markdown variants are active, override priorities, or gate a rule per-app — jump to Feature-Owned Markdown Rules for the manual path.

That's the whole surface in under a minute. Type # , type ->, watch them land.

Feature-Owned Markdown Rules

Feature packages export semantic rule families. Each family exposes one or more factory functions that return a concrete rule you pass into the matching plugin's inputRules.

Basic Blocks

Basic block rules ship with @platejs/basic-nodes. Register them per plugin.

Headings. HeadingRules.markdown() is the same factory for H1 through H6. It derives the markdown prefix from the plugin key (#, ##, ###, ...), so you pass it once on each heading plugin.

import { HeadingRules } from '@platejs/basic-nodes';
import { H1Plugin, H2Plugin, H3Plugin } from '@platejs/basic-nodes/react';
 
H1Plugin.configure({
  inputRules: [HeadingRules.markdown()],
}),
H2Plugin.configure({
  inputRules: [HeadingRules.markdown()],
}),
H3Plugin.configure({
  inputRules: [HeadingRules.markdown()],
}),
// ... same for H4, H5, H6Copy

Blockquote. BlockquoteRules.markdown() fires on > followed by space and wraps the current block. Because blockquote is a wrapper/container node, the rule nests cleanly inside an existing quote instead of trying to retag the paragraph in place. The rule is gated with enabled so it won't fire inside a code block.

import { BlockquoteRules } from '@platejs/basic-nodes';
import { BlockquotePlugin } from '@platejs/basic-nodes/react';
 
BlockquotePlugin.configure({
  inputRules: [BlockquoteRules.markdown()],
}),Copy

Horizontal rule. HorizontalRuleRules.markdown() takes a variant so you can register more than one trigger.

import { HorizontalRuleRules } from '@platejs/basic-nodes';
import { HorizontalRulePlugin } from '@platejs/basic-nodes/react';
 
HorizontalRulePlugin.configure({
  inputRules: [
    HorizontalRuleRules.markdown({ variant: '-' }),
    HorizontalRuleRules.markdown({ variant: '_' }),
  ],
}),Copy

--- and ___ both create a horizontal rule. Register only the variants you want to support.

Basic Marks

Mark rules live in the same package. Each factory returns a single rule, so register one per trigger you want to support.

Bold, italic, underline.

import {
  BoldRules,
  ItalicRules,
  UnderlineRules,
} from '@platejs/basic-nodes';
import {
  BoldPlugin,
  ItalicPlugin,
  UnderlinePlugin,
} from '@platejs/basic-nodes/react';
 
BoldPlugin.configure({
  inputRules: [
    BoldRules.markdown({ variant: '*' }),
    BoldRules.markdown({ variant: '_' }),
  ],
}),
ItalicPlugin.configure({
  inputRules: [
    ItalicRules.markdown({ variant: '*' }),
    ItalicRules.markdown({ variant: '_' }),
  ],
}),
UnderlinePlugin.configure({
  inputRules: [UnderlineRules.markdown()],
}),Copy

Register both * and _ variants to accept **bold** and __bold__. Underline uses a fixed __x__ form, so its factory takes no options.

Combos. MarkComboRules.markdown() is a single factory that covers multi-delimiter patterns like ***bold italic***. Register combos alongside the single-mark rules on the plugin that owns the dominant mark.

import { BoldRules, MarkComboRules } from '@platejs/basic-nodes';
import { BoldPlugin } from '@platejs/basic-nodes/react';
 
BoldPlugin.configure({
  inputRules: [
    BoldRules.markdown({ variant: '*' }),
    BoldRules.markdown({ variant: '_' }),
    MarkComboRules.markdown({ variant: 'boldItalic' }),
    MarkComboRules.markdown({ variant: 'boldUnderline' }),
    MarkComboRules.markdown({ variant: 'boldItalicUnderline' }),
    MarkComboRules.markdown({ variant: 'italicUnderline' }),
  ],
}),Copy

Combo variants: 'boldItalic' | 'boldUnderline' | 'boldItalicUnderline' | 'italicUnderline'.

Inline code, strikethrough, subscript, superscript, highlight.

import {
  CodeRules,
  HighlightRules,
  StrikethroughRules,
  SubscriptRules,
  SuperscriptRules,
} from '@platejs/basic-nodes';
import {
  CodePlugin,
  HighlightPlugin,
  StrikethroughPlugin,
  SubscriptPlugin,
  SuperscriptPlugin,
} from '@platejs/basic-nodes/react';
 
CodePlugin.configure({
  inputRules: [CodeRules.markdown()],
}),
StrikethroughPlugin.configure({
  inputRules: [StrikethroughRules.markdown()],
}),
SubscriptPlugin.configure({
  inputRules: [SubscriptRules.markdown()],
}),
SuperscriptPlugin.configure({
  inputRules: [SuperscriptRules.markdown()],
}),
HighlightPlugin.configure({
  inputRules: [
    HighlightRules.markdown({ variant: '==' }),
    HighlightRules.markdown({ variant: '≡' }),
  ],
}),Copy

Inline code uses `x`. Strikethrough uses ~~x~~. Subscript is ~x~. Superscript is ^x^. Highlight accepts ==x== or ≡x≡ — pick either, both, or pass a different variant.

Code Blocks

Code blocks are fenced, which makes them different from simple marks or block prefixes. They ship as a block fence rule, and you must pass on to pick when the fence commits.

import { CodeBlockRules } from '@platejs/code-block';
import { CodeBlockPlugin } from '@platejs/code-block/react';
 
CodeBlockPlugin.configure({
  inputRules: [CodeBlockRules.markdown({ on: 'match' })],
}),Copy

on: 'match' commits the moment the fence text becomes complete — typing the third backtick of the opening fence converts the paragraph to a code block immediately.

CodeBlockPlugin.configure({
  inputRules: [CodeBlockRules.markdown({ on: 'break' })],
}),Copy

on: 'break' waits for you to press Enter after the fence is complete. Same matcher, different commit point.

If you need to suppress code blocks inside a specific context, pass enabled:

CodeBlockRules.markdown({
  on: 'match',
  enabled: ({ editor }) => !isInsideSomeCustomContainer(editor),
}),Copy

Lists

List rules live in @platejs/list and register on the single ListPlugin. Each factory targets one shape.

import {
  BulletedListRules,
  OrderedListRules,
  TaskListRules,
} from '@platejs/list';
import { ListPlugin } from '@platejs/list/react';
 
ListPlugin.configure({
  inputRules: [
    BulletedListRules.markdown({ variant: '-' }),
    BulletedListRules.markdown({ variant: '*' }),
    OrderedListRules.markdown({ variant: '.' }),
    OrderedListRules.markdown({ variant: ')' }),
    TaskListRules.markdown({ checked: false }),
    TaskListRules.markdown({ checked: true }),
  ],
}),Copy

• BulletedListRules.markdown({ variant }) accepts '-' or '*'.
• OrderedListRules.markdown({ variant }) accepts '.' or ')'. The rule parses the leading number and starts the list from it, so 3. creates a list that begins at 3.
• TaskListRules.markdown({ checked }) maps [] to an unchecked task and [x] to a checked task.

All list rules use enabled to opt out inside code blocks.

Math

Math has two shapes: inline $x$ and block $$x$$. They're intentionally split so apps can enable one without the other.

import { MathRules } from '@platejs/math';
import { EquationPlugin, InlineEquationPlugin } from '@platejs/math/react';
 
InlineEquationPlugin.configure({
  inputRules: [MathRules.markdown({ variant: '$' })],
}),
EquationPlugin.configure({
  inputRules: [MathRules.markdown({ variant: '$$', on: 'break' })],
}),Copy

variant: '$' is inline — a delimited mark rule. variant: '$$' is a block fence, so — like CodeBlockRules — it takes on: 'match' | 'break'. The example uses on: 'break', which commits the block equation when you press Enter after the fence.

Links

Link rules are not just substitutions — they validate URLs and wrap text with a full link node.

import { LinkRules } from '@platejs/link';
import { LinkPlugin } from '@platejs/link/react';
 
LinkPlugin.configure({
  inputRules: [
    LinkRules.markdown(),
    LinkRules.autolink({ variant: 'paste' }),
    LinkRules.autolink({ variant: 'space' }),
    LinkRules.autolink({ variant: 'break' }),
  ],
}),Copy

• LinkRules.markdown() handles [label](https://...).
• LinkRules.autolink({ variant: 'paste' }) turns a pasted URL into a link.
• LinkRules.autolink({ variant: 'space' }) detects a URL when you type a trailing space.
• LinkRules.autolink({ variant: 'break' }) detects a URL when you press Enter.

Register whichever variants you want — you can pick one, two, or all four.

That's the full feature-owned catalog. Every package you add contributes its own rules; the editor picks them up the moment you register them.

Local Copied Shortcuts

Sometimes you want small text substitutions — smart quotes, arrows, fractions, trademarks — that don't belong to any feature package. Use createTextSubstitutionInputRule for this.

createTextSubstitutionInputRule

The helper takes a patterns array and builds a single insertText rule. Each pattern has a match (what you type) and a format (what you end up with).

import {
  createSlatePlugin,
  createTextSubstitutionInputRule,
  KEYS,
  type SlateEditor,
} from 'platejs';
 
const isInCodeBlock = (editor: SlateEditor) =>
  editor.api.some({
    match: { type: [editor.getType(KEYS.codeBlock)] },
  });
 
const arrowsRule = createTextSubstitutionInputRule({
  enabled: ({ editor }) => !isInCodeBlock(editor),
  patterns: [
    { format: '→', match: '->' },
    { format: '←', match: '<-' },
    { format: '⇒', match: '=>' },
    { format: '⇐', match: ['<=', '≤='] },
  ],
});
 
export const ArrowsShortcutsPlugin = createSlatePlugin({
  key: 'arrowsShortcuts',
  inputRules: [arrowsRule],
});Copy

A few details worth knowing:

• match can be a string or an array of strings — all entries are checked before formatting.
• format can be a single string or a [open, close] tuple. A tuple wraps the typed text as open + content + close, useful for smart quotes and brackets.
• trigger defaults to the last character of each match, which is almost always what you want. Override it only if you need a distinct commit char.
• enabled gates the whole rule, so you don't have to guard each pattern individually.

Use AutoformatKit As A Starting Point

The autoformat-kit.tsx file in Plate's registry wires up a full set of substitutions — arrows, comparisons, equalities, fractions, legal symbols, smart quotes, sub/superscript numerals — all gated against code blocks. Copy it into your app and edit the patterns.

import {
  createSlatePlugin,
  createTextSubstitutionInputRule,
  KEYS,
  type SlateEditor,
} from 'platejs';
 
const isTextSubstitutionBlocked = (editor: SlateEditor) =>
  editor.api.some({
    match: { type: [editor.getType(KEYS.codeBlock)] },
  });
 
const createAutoformatTextSubstitutionRule = ({
  patterns,
}: {
  patterns: Parameters<typeof createTextSubstitutionInputRule>[0]['patterns'];
}) =>
  createTextSubstitutionInputRule({
    enabled: ({ editor }) => !isTextSubstitutionBlocked(editor),
    patterns,
  });
 
const legalRule = createAutoformatTextSubstitutionRule({
  patterns: [
    { format: '™', match: ['(tm)', '(TM)'] },
    { format: '®', match: ['(r)', '(R)'] },
    { format: '©', match: ['(c)', '(C)'] },
  ],
});
 
const smartQuotesRule = createAutoformatTextSubstitutionRule({
  patterns: [
    { format: ['“', '”'], match: '"' },
    { format: ['‘', '’'], match: "'" },
  ],
});
 
const AutoformatShortcutsPlugin = createSlatePlugin({
  key: 'autoformatShortcuts',
  inputRules: [legalRule, smartQuotesRule /* ...more */],
});
 
export const AutoformatKit = [AutoformatShortcutsPlugin];Copy

When To Reach For defineInputRule

Text substitution covers the glyph-for-glyph case. When you need more — reading the current block, dispatching a richer transform, or detecting a pattern that isn't a simple character match — drop down to defineInputRule or one of the low-level builders.

Custom Rules

Everything above is sugar on top of three low-level authoring surfaces:

• defineInputRule, an identity function that types a raw rule inline.
• The specialized builders: createMarkInputRule, createBlockStartInputRule, createBlockFenceInputRule, createTextSubstitutionInputRule.
• createRuleFactory, the package-authoring helper used to expose semantic families like MathRules.markdown(...) or LinkRules.autolink(...) without re-declaring shared runtime fields.

Use this section when none of the shipped families fit your need or when you're authoring your own reusable rule family.

Register Explicit Rule Instances

Rules are concrete objects. You pass them into inputRules exactly as-is. To override a field like priority or enabled on a finished instance, spread the rule and replace the field:

import { HeadingRules } from '@platejs/basic-nodes';
import { LinkRules } from '@platejs/link';
import { H1Plugin } from '@platejs/basic-nodes/react';
import { LinkPlugin } from '@platejs/link/react';
 
H1Plugin.configure({
  inputRules: [HeadingRules.markdown()],
}),
LinkPlugin.configure({
  inputRules: [
    LinkRules.markdown(),
    { ...LinkRules.autolink({ variant: 'paste' }), priority: 200 },
  ],
}),Copy

Why the spread? Package factories are intentionally narrow — most don't take a priority option. Overriding is the caller's job, and spreading the returned rule keeps it obvious that you're changing one field on an already-built instance.

The same pattern works for enabled. If a family ships with a sensible default but you need stricter gating in one app, spread the rule and override:

{
  ...BlockquoteRules.markdown(),
  enabled: ({ editor }) => !isInsideCallout(editor),
},Copy

Plugin-Side Factories

For plugin authors, the inputRules option also accepts a function that receives a rule builder. Use this form when your rules depend on plugin-local state or when you want your rule wiring to live next to the plugin's types.

import { createSlatePlugin } from 'platejs';
 
const CustomPlugin = createSlatePlugin({
  key: 'custom',
  inputRules: ({ rule }) => [
    rule.mark({
      trigger: '*',
      start: '*',
    }),
    rule.blockStart({
      trigger: ' ',
      match: '>',
      mode: 'wrap',
      node: 'blockquote',
    }),
    rule.blockFence({
      fence: '```',
      on: 'match',
      apply: (context, match) => {
        // convert to code block
      },
    }),
  ],
});Copy

The rule builder exposes six primitives:

Use the factory form when you need that co-location; use the array form when you just want to register a handful of concrete instances.

Author A Rule Family

When you're shipping a package, you usually want a public factory like MyNodeRules.markdown(...) that takes a narrow options object and hides the low-level rule plumbing. Reach for createRuleFactory.

import { createRuleFactory, KEYS } from 'platejs';
 
export const BlockquoteRules = {
  markdown: createRuleFactory<{}, { marker: string }>({
    type: 'blockStart',
    marker: '>',
    trigger: ' ',
    mode: 'wrap',
    match: ({ marker }) => marker,
    enabled: ({ editor }) =>
      !editor.api.some({ match: { type: [editor.getType(KEYS.codeBlock)] } }),
  }),
};Copy

A few things to notice:

• type picks the underlying builder. Use 'mark', 'blockStart', 'blockFence', or 'textSubstitution'.
• The two generic parameters model your public API: TRequired (the first) are options callers must pass; TDefaults (the second) are options you supply a default for — here, marker: '>'.
• Factory values can be plain values ('>') or functions of the input (({ marker }) => marker). The input includes the runtime context, your defaults, and any required options the caller passes.
• For blockStart, core already owns the base match payload: { range, text }. If you provide resolveMatch, return only your extra fields — core merges them onto the base payload before apply runs.
• enabled and priority stay available as runtime overrides on the returned rule instance — callers can override them even when your factory sets a default.

That's the pattern every *Rules.markdown(...) family in Plate uses. Clone it when you need your own.

Done. Between defineInputRule, the four specialized builders, the plugin-side rule builder, and createRuleFactory, every rule in Plate — yours included — comes from the same small core.

How Rule Execution Works

Input rules run inside the insertText, insertBreak, and insertData transforms. For each call, the runtime walks every registered rule for that target in priority order, and the first rule that passes enabled and produces a non-undefined resolve gets to call apply.

Targets

A rule's target field picks which lane it runs in.

The high-level factories set target for you:

• createMarkInputRule and createBlockStartInputRule always produce insertText rules.
• createBlockFenceInputRule produces an insertText rule when on: 'match' and an insertBreak rule when on: 'break'.
• createTextSubstitutionInputRule always produces an insertText rule.

defineInputRule lets you pick any target by setting the target field directly.

Selection Context

Every enabled, resolve, and apply call receives a context object with the live editor, the selection state, and a handful of lazy helpers.

The get* helpers are memoized — calling them twice inside the same rule evaluation doesn't recompute. That matters because multiple rules can share the same evaluation pass.

Target-specific context fields:

• insertText rules additionally receive text, cause: 'insertText', and an insertText callback for default fallthrough.
• insertBreak rules receive cause: 'insertBreak' and an insertBreak callback.
• insertData rules receive data: DataTransfer, text, cause: 'insertData', and an insertData callback.

Lifecycle

For each transform call, the runtime walks rules in priority order (highest first). For each rule, it runs the following steps:

1. enabled. A boolean gate. If it returns false, skip to the next rule.
2. resolve. Computes a match payload. If it returns undefined, skip to the next rule.
3. apply. Performs the transform. If it returns false, the runtime treats the rule as not consumed and continues; any other return value consumes the input and short-circuits the rest of the walk.

If no rule consumes the input, the default Slate transform runs as normal.

API Reference

Low-level surface. Reach for this when the high-level factories don't cover your case. Everything below is exported from platejs.

Rule Targets

type InputRuleTarget = 'insertText' | 'insertBreak' | 'insertData';Copy

defineInputRule

Identity function that types a rule inline.

function defineInputRule<TRule extends AnyInputRule>(rule: TRule): TRule;Copy

import { defineInputRule } from 'platejs';
 
const myRule = defineInputRule({
  target: 'insertText',
  trigger: ')',
  resolve: (context) => {
    // compute and return a match payload, or undefined to skip
  },
  apply: (context, match) => {
    // perform the transform
  },
});Copy

Use it when you want a raw rule object typed against InsertTextInputRule, InsertBreakInputRule, or InsertDataInputRule without going through a builder.

createRuleFactory

Package-facing helper for semantic rule families. Use it when you want to expose a narrow public factory like BlockquoteRules.markdown(...), keep shared runtime fields like enabled and priority, and hide the low-level rule construction details.

import { createRuleFactory } from 'platejs';
 
export const BlockquoteRules = {
  markdown: createRuleFactory<{}, { marker: string }>({
    type: 'blockStart',
    marker: '>',
    trigger: ' ',
    match: ({ marker }) => marker,
    mode: 'wrap',
    enabled: ({ editor }) => !isInCodeBlock(editor),
  }),
};Copy

The returned function is your public rule family. Concrete values in the config become default public options (marker: '>'), while the generic type parameters let you model required options and defaults for the family. The created rule instance still supports the shared runtime overrides: enabled and priority.

createMarkInputRule

Delimited inline marks (**bold**, `code`, ~~strike~~).

function createMarkInputRule(config: {
  start: string;
  end?: string;
  trigger: string;
  mark?: string;
  marks?: string[];
  trim?: 'allow' | 'reject';
  enabled?: (context: InsertTextInputRuleContext) => boolean;
  priority?: number;
}): InsertTextInputRule;Copy

import { createMarkInputRule } from 'platejs';
 
createMarkInputRule({
  start: '**',
  end: '*',
  trigger: '*',
});Copy

start is the opening delimiter. end is an optional closing delimiter; when omitted, the rule does not look for a separate closing delimiter before the trigger. trigger is the character that commits the match. trim: 'reject' refuses spans with leading or trailing whitespace. mark and marks restrict which mark(s) the rule applies.

createBlockStartInputRule

Block-start patterns typed at the beginning of a block (# , > , - , 1. ).

function createBlockStartInputRule<TMatch extends object = {}>(config: {
  trigger: string;
  match:
    | RegExp
    | string
    | ((context: InsertTextInputRuleContext) => RegExp | string | undefined);
  mode?: 'set' | 'toggle' | 'wrap';
  node?: string;
  removeMatchedText?: boolean;
  resolveMatch?: (args: {
    match: RegExpMatchArray | string;
    range: TRange;
    text: string;
  }) => TMatch | undefined;
  apply?: (
    context: InsertTextInputRuleContext,
    match: BlockStartInputRuleMatch & TMatch
  ) => boolean | void;
  enabled?: (context: InsertTextInputRuleContext) => boolean;
  priority?: number;
}): InsertTextInputRule<TMatch>;Copy

import { createBlockStartInputRule } from 'platejs';
 
createBlockStartInputRule({
  trigger: ' ',
  match: '>',
  mode: 'wrap',
});Copy

• trigger is the commit character — typically ' '.
• match is the block-start text: a string, a RegExp, or a function that returns one based on context.
• mode picks the transform: 'set' replaces the block type, 'toggle' flips it, 'wrap' wraps the block in a new element.
• node is the target element type used by mode.
• apply overrides the built-in transform entirely — supply your own when none of the modes fit. That also means you own matched-text cleanup; if you still want the shorthand removed, delete match.range yourself.
• resolveMatch returns extra fields only. Core still provides the base { range, text } payload automatically, and apply receives the merged object.

createBlockFenceInputRule

Fenced block patterns like triple-backtick code fences or $$ math fences.

function createBlockFenceInputRule<TMatch>(config: {
  fence: string;
  on: 'break' | 'match';
  apply: (context: SelectionInputRuleContext, match: TMatch) => boolean | void;
  block?: string;
  resolveMatch?: (args: {
    fence: string;
    path: Path;
    range: TRange;
    text: string;
  }) => TMatch | undefined;
  enabled?: (context: SelectionInputRuleContext) => boolean;
  priority?: number;
}): InsertTextInputRule<TMatch> | InsertBreakInputRule<TMatch>;Copy

import { createBlockFenceInputRule } from 'platejs';
 
createBlockFenceInputRule({
  fence: '```',
  on: 'match',
  apply: (context, match) => {
    // perform the replacement
  },
});Copy

on: 'match' commits when the fence becomes complete inside the current paragraph. on: 'break' commits when Enter is pressed after the fence is complete — useful when the user may want to type more before committing.

The runtime owns the matcher: it checks that the selection is collapsed, the cursor is at the block's end, and the block text equals fence. If you pass block, the matcher also requires that block type. You own apply, which performs the replacement. The returned rule targets insertText when on: 'match' and insertBreak when on: 'break'.

createTextSubstitutionInputRule

Glyph-for-glyph substitutions.

function createTextSubstitutionInputRule(config: {
  patterns: Array<{
    format: readonly [string, string] | string;
    match: readonly string[] | string;
    trigger?: readonly string[] | string;
  }>;
  enabled?: (context: InsertTextInputRuleContext) => boolean;
  priority?: number;
}): InsertTextInputRule;Copy

import { createTextSubstitutionInputRule } from 'platejs';
 
createTextSubstitutionInputRule({
  patterns: [
    { format: '→', match: '->' },
    { format: ['«', '»'], match: '<<' },
  ],
});Copy

format is either a replacement string or a [open, close] tuple that wraps the typed content. match is a string or array of strings that trigger the replacement. trigger defaults to the last character of each match and rarely needs overriding.

matchDelimitedInline

Low-level matcher used under createMarkInputRule. Returns a { content, deleteRange } match for a delimited inline pattern, or undefined.

import { matchDelimitedInline } from 'platejs';
 
const match = matchDelimitedInline(context, {
  open: '**',
  close: '*',
  // optional: boundaryRe, followRe, rejectRepeatedOpen, requireClosingDelimiter, trim
});Copy

Use it when you're authoring a custom insertText rule that needs the same matching shape as a mark without going through createMarkInputRule.

matchBlockStart / matchBlockFence

Companion matchers for block-start and block-fence rules. Both take the current context plus a matcher config and return a match payload or undefined. Use them when you want the matcher logic without the factory's apply wiring.

import { matchBlockFence, matchBlockStart } from 'platejs';
 
const startMatch = matchBlockStart(context, { match: '>' });
const fenceMatch = matchBlockFence(context, { fence: '```' });Copy

Package Rule Families

Every family below is a single export from its package. Each .markdown() (or .autolink()) call returns a concrete rule you pass into the matching plugin's inputRules.

Each family's factory takes a narrow options object — see the per-section examples above for the exact shape.