remark-lint-no-unused-definitions

What is remark-lint-no-unused-definitions?

The remark-lint-no-unused-definitions package is a plugin for remark-lint that checks for unused definitions in Markdown files. It helps maintain clean and efficient Markdown documents by ensuring that all definitions are used.

What are remark-lint-no-unused-definitions's main functionalities?

Linting for Unused Definitions

The primary feature of remark-lint-no-unused-definitions is to identify and report definitions in Markdown files that are declared but not used. In the provided code sample, the definition `[unused]: https://unused.com` is not used anywhere in the document, and the plugin would flag this as an issue.

```markdown
# Example

This is a [link][example].

[example]: https://example.com

This is an unused definition:

[unused]: https://unused.com
```

Other packages similar to remark-lint-no-unused-definitions

remark-lint

remark-lint is a general-purpose Markdown linter that provides a wide range of rules for checking Markdown files. While it does not specifically focus on unused definitions, it can be extended with plugins like remark-lint-no-unused-definitions to cover this functionality.

markdownlint

markdownlint is a Node.js style checker and linting tool for Markdown files. It offers a variety of rules to enforce consistent Markdown style, including some that overlap with the functionality of remark-lint-no-unused-definitions, such as checking for unused links and references.

markdown-it

markdown-it is a Markdown parser that can be extended with plugins to add various functionalities, including linting. While it is primarily focused on parsing, plugins can be added to perform checks similar to those provided by remark-lint-no-unused-definitions.

README

remark-lint-no-unused-definitions

remark-lint rule to warn when unreferenced definitions are used.

Contents

• What is this?
• When should I use this?
• Presets
• Install
• Use
• API
  • unified().use(remarkLintNoUnusedDefinitions)
• Recommendation
• Examples
• Compatibility
• Contribute
• License

What is this?

This package checks that definitions are referenced.

When should I use this?

You can use this package to check definitions.

Presets

This plugin is included in the following presets:

Preset	Options
remark-preset-lint-recommended

Install

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

npm install remark-lint-no-unused-definitions

In Deno with esm.sh:

import remarkLintNoUnusedDefinitions from 'https://esm.sh/remark-lint-no-unused-definitions@4'

In browsers with esm.sh:

<script type="module">
  import remarkLintNoUnusedDefinitions from 'https://esm.sh/remark-lint-no-unused-definitions@4?bundle'
</script>

Use

On the API:

import remarkLint from 'remark-lint'
import remarkLintNoUnusedDefinitions from 'remark-lint-no-unused-definitions'
import remarkParse from 'remark-parse'
import remarkStringify from 'remark-stringify'
import {read} from 'to-vfile'
import {unified} from 'unified'
import {reporter} from 'vfile-reporter'

const file = await read('example.md')

await unified()
  .use(remarkParse)
  .use(remarkLint)
  .use(remarkLintNoUnusedDefinitions)
  .use(remarkStringify)
  .process(file)

console.error(reporter(file))

On the CLI:

remark --frail --use remark-lint --use remark-lint-no-unused-definitions .

On the CLI in a config file (here a package.json):

 …
 "remarkConfig": {
   "plugins": [
     …
     "remark-lint",
+    "remark-lint-no-unused-definitions",
     …
   ]
 }
 …

API

This package exports no identifiers. It exports no additional TypeScript types. The default export is remarkLintNoUnusedDefinitions.

unified().use(remarkLintNoUnusedDefinitions)

Warn when unreferenced definitions are used.

Parameters

There are no options.

Returns

Transform (Transformer from unified).

Recommendation

Unused definitions do not contribute anything, so they can be removed.

Examples

ok.md

In

[Mercury][]

[mercury]: https://example.com/mercury/

Out

No messages.

not-ok.md

In

[mercury]: https://example.com/mercury/

Out

1:1-1:40: Unexpected unused definition, expected no definition or one or more references to `mercury`

gfm.md

In

👉 Note: this example uses GFM (remark-gfm).

Mercury[^mercury] is a planet.

[^Mercury]:
    **Mercury** is the first planet from the Sun and the smallest
    in the Solar System.
[^Venus]:
    **Venus** is the second planet from
    the Sun.

Out

6:1-8:13: Unexpected unused footnote definition, expected no definition or one or more footnote references to `venus`

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, remark-lint-no-unused-definitions@4, compatible with Node.js 16.

Contribute

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.

License

MIT © Titus Wormer