rehype-shift-heading

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[rehype][] plugin to change the rank of headings.

Contents

* What is this?
* When should I use this?
* Install
* Use
* API
* [unified().use(rehypeShiftHeading[, options])](#unifieduserehypeshiftheading-options)
* Options
* Types
* Compatibility
* Security
* Related
* Contribute
* License

What is this?

This package is a [unified][] ([rehype][]) plugin to change the rank (also known
as depth or level) of headings (so

through

).
You can increase (by passing a positive number) or decrease (negative number)
all headings.

unified is a project that transforms content with abstract syntax trees
(ASTs).
rehype adds support for HTML to unified.
hast is the HTML AST that rehype uses.
This is a rehype plugin that changes headings in the tree.

When should I use this?

This plugin is particularly useful when merging documents into each other.
For example, when injecting a readme.md that starts with an

into a
site that uses an

for the title of the website.
This plugin can be used to shift all the headings inside the readme.

This plugin is built on [hast-util-shift-heading][hast-util-shift-heading],
which does the work on syntax trees.
rehype focusses on making it easier to transform content by abstracting such
internals away.

Install

This package is [ESM only][esm].
In Node.js (version 16+), install with [npm][]:

``sh
npm install rehype-shift-heading
`

In Deno with [esm.sh][esmsh]:

`js
import rehypeShiftHeading from 'https://esm.sh/rehype-shift-heading@2'
`

In browsers with [esm.sh][esmsh]:

`html

`

Use

Say our module example.js looks as follows:

`js
import {rehype} from 'rehype'
import rehypeShiftHeading from 'rehype-shift-heading'

const file = await rehype()
.data('settings', {fragment: true})
.use(rehypeShiftHeading, {shift: 1})
.process('

Alpha!

')

console.log(String(file))
`

Now, running node example yields:

`html


Alpha!


`

API

This package exports no identifiers.
The default export is [rehypeShiftHeading][api-rehype-shift-heading].

$3

Change the rank (depth, level) of headings.

Does not shift past h1 and h6.

###### Parameters

* options ([Options][api-options], optional)
— configuration

###### Returns

Transform ([Transformer][unified-transformer]).

$3

Configuration (TypeScript type).

###### Fields

* shift (number, default: 0)
— number to shift headings; can be negative to decrease heading levels

Types

This package is fully typed with [TypeScript][].
It exports the additional type [Options][api-options].

Compatibility

Projects maintained by the unified collective are compatible with maintained
versions of Node.js.

When we cut a new major release, we drop support for unmaintained versions of
Node.
This means we try to keep the current release line, rehype-shift-heading@^2,
compatible with Node.js 16.

This plugin works with rehype-parse version 1+, rehype-stringify version 1+,
rehype version 1+, and unified version 4+.

Security

Use of rehype-shift-heading is safe.

Related

* rehype-slug
— add ids to headings
* rehype-autolink-headings
— add links to headings

Contribute

See [contributing.md][contributing] in [rehypejs/.github][health] for ways
to get started.
See [support.md`][support] for ways to get help.

This project has a [code of conduct][coc].
By interacting with this repository, organization, or community you agree to
abide by its terms.

License

[MIT][license] © [Titus Wormer][author]

[build-badge]: https://github.com/rehypejs/rehype-shift-heading/workflows/main/badge.svg

[build]: https://github.com/rehypejs/rehype-shift-heading/actions

[coverage-badge]: https://img.shields.io/codecov/c/github/rehypejs/rehype-shift-heading.svg

[coverage]: https://codecov.io/github/rehypejs/rehype-shift-heading

[downloads-badge]: https://img.shields.io/npm/dm/rehype-shift-heading.svg

[downloads]: https://www.npmjs.com/package/rehype-shift-heading

[size-badge]: https://img.shields.io/bundlejs/size/rehype-shift-heading

[size]: https://bundlejs.com/?q=rehype-shift-heading

[sponsors-badge]: https://opencollective.com/unified/sponsors/badge.svg

[backers-badge]: https://opencollective.com/unified/backers/badge.svg

[collective]: https://opencollective.com/unified

[chat-badge]: https://img.shields.io/badge/chat-discussions-success.svg

[chat]: https://github.com/rehypejs/rehype/discussions

[npm]: https://docs.npmjs.com/cli/install

[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c

[esmsh]: https://esm.sh

[health]: https://github.com/rehypejs/.github

[contributing]: https://github.com/rehypejs/.github/blob/HEAD/contributing.md

[support]: https://github.com/rehypejs/.github/blob/HEAD/support.md

[coc]: https://github.com/rehypejs/.github/blob/HEAD/code-of-conduct.md

[license]: license

[author]: https://wooorm.com

[typescript]: https://www.typescriptlang.org

[rehype]: https://github.com/rehypejs/rehype

[unified]: https://github.com/unifiedjs/unified

[unified-transformer]: https://github.com/unifiedjs/unified?tab=readme-ov-file#transformer

[hast-util-shift-heading]: https://github.com/syntax-tree/hast-util-shift-heading

[api-options]: #options

[api-rehype-shift-heading]: #unifieduserehypeshiftheading-options