Project: remarkjs/remark-defsplit

Package: remark-defsplit@4.0.1

  1. Dependents: 0
  2. remark plugin to change links and images to references with separate definitions
  1. remark 193
  2. unified 178
  3. markdown 140
  4. plugin 138
  5. mdast 87
  6. remark-plugin 76
  7. definition 15
  8. link 15
  9. image 12
  10. reference 12
  11. destination 2
  12. extract 2


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remark plugin to change links and images to references with separate definitions.


What is this?

This package is a unified (remark) plugin to turn links ([text](url)) and images (![alt](url)) into references ([text][id], ![alt][id]) and definitions ([id]: url).

unified is a project that transforms content with abstract syntax trees (ASTs). remark adds support for markdown to unified. mdast is the markdown AST that remark uses. This is a remark plugin that transforms mdast.

When should I use this?

This project is useful when you want to transform markdown and prefer that it uses references and definitions. Long URLs in source code can make reading markdown difficult. References and definitions improve that by moving those URLs into definitions, outside of paragraphs.

This plugin is very similar to the alternative remark-reference-links. The difference is that that plugin generates numeric identifiers at the end of the document, whereas this plugin generates identifiers based on hostnames of URLs at the end of each section.

A different plugin, remark-inline-links, does the inverse: turn references and definitions into links and images.


This package is ESM only. In Node.js (version 12.20+, 14.14+, or 16.0+), install with npm:

npm install remark-defsplit

In Deno with esm.sh:

import remarkDefsplit from 'https://esm.sh/remark-defsplit@4'

In browsers with esm.sh:

<script type="module">
  import remarkDefsplit from 'https://esm.sh/remark-defsplit@4?bundle'


Say we have the following file example.md:

# Some project


## Section

[A link](https://example.com)

And our module example.js looks as follows:

import {read} from 'to-vfile'
import {remark} from 'remark'
import remarkDefsplit from 'remark-defsplit'


async function main() {
  const file = await remark()
    .process(await read('example.md'))


Now running node example.js yields:

# Some project


[github-1]: https://github.com/remarkjs/remark-defsplit/workflows/main/badge.svg

[github-2]: https://github.com/remarkjs/remark-defsplit/actions

## Section

[A link][example-1]

[example-1]: https://example.com

👉 Note: Observe that definitions are added at the end of each section and that IDs are generated based on the hostname of URLs.


This package exports no identifiers. The default export is remarkDefsplit.

unified().use(remarkDefsplit[, options])

Plugin to change links and images to references with separate definitions.


Identifiers to use for new definitions instead of autogenerated ones (string or string[], default: []). For example, when given one ID, then the first link or image will use that ID for the reference and definition. When another link or image is seen, it’ll get an autogenerated ID.


This package is fully typed with TypeScript. It exports an Options type, which specifies the interface of the accepted options.


Projects maintained by the unified collective are compatible with all maintained versions of Node.js. As of now, that is Node.js 12.20+, 14.14+, and 16.0+. Our projects sometimes work with older versions, but this is not guaranteed.

This plugin works with unified version 6+ and remark version 7+.


Use of remark-defsplit does not involve rehype (hast) or user content so there are no openings for cross-site scripting (XSS) attacks.


See contributing.md in remarkjs/.github for ways to get started. See support.md for ways to get help.

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


MIT © Eugene Sharygin