remark-lint-emphasis-marker

remark-lint rule to warn when emphasis markers are inconsistent.

Contents

• What is this?
• When should I use this?
• Presets
• Install
• Use
• API
  • unified().use(remarkLintEmphasisMarker[, options])
  • Marker
  • Options
• Recommendation
• Fix
• Examples
• Compatibility
• Contribute
• License

What is this?

This package checks the style of emphasis markers.

When should I use this?

You can use this package to check that emphasis is consistent.

Presets

This plugin is included in the following presets:

Preset	Options
remark-preset-lint-consistent	'consistent'
remark-preset-lint-markdown-style-guide	'*'

Install

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

npm install remark-lint-emphasis-marker

In Deno with esm.sh:

import remarkLintEmphasisMarker from 'https://esm.sh/remark-lint-emphasis-marker@4'

In browsers with esm.sh:

<script type="module">
  import remarkLintEmphasisMarker from 'https://esm.sh/remark-lint-emphasis-marker@4?bundle'
</script>

Use

On the API:

import remarkLint from 'remark-lint'
import remarkLintEmphasisMarker from 'remark-lint-emphasis-marker'
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(remarkLintEmphasisMarker)
  .use(remarkStringify)
  .process(file)

console.error(reporter(file))

On the CLI:

remark --frail --use remark-lint --use remark-lint-emphasis-marker .

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

 …
 "remarkConfig": {
   "plugins": [
     …
     "remark-lint",
+    "remark-lint-emphasis-marker",
     …
   ]
 }
 …

API

This package exports no identifiers. It exports the TypeScript types Marker and Options. The default export is remarkLintEmphasisMarker.

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

Warn when emphasis markers are inconsistent.

Parameters

• options (Options, default: 'consistent') — preferred style or whether to detect the first style and warn for further differences

Returns

Transform (Transformer from unified).

Marker

Marker (TypeScript type).

Type

type Marker = '*' | '_'

Options

Configuration (TypeScript type).

Type

type Options = Marker | 'consistent'

Recommendation

Whether asterisks or underscores are used affects how and whether emphasis works. Underscores are sometimes used to represent normal underscores inside words, so there are extra rules in markdown to support that. Asterisks are not used in natural language, so they don’t need these rules, and thus can form emphasis in more cases. Asterisks can also be used as the marker of more constructs than underscores: lists. Due to having simpler parsing rules, looking more like syntax, and that they can be used for more constructs, it’s recommended to prefer asterisks.

Fix

remark-stringify formats emphasis with asterisks by default. Pass emphasis: '_' to always use underscores.

Examples

ok-asterisk.md

When configured with '*'.

In

*Mercury*.

Out

No messages.

not-ok-asterisk.md

When configured with '*'.

In

_Mercury_.

Out

1:1-1:10: Unexpected emphasis marker `_`, expected `*`

ok-underscore.md

When configured with '_'.

In

_Mercury_.

Out

No messages.

not-ok-underscore.md

When configured with '_'.

In

*Mercury*.

Out

1:1-1:10: Unexpected emphasis marker `*`, expected `_`

not-ok-consistent.md

In

*Mercury* and _Venus_.

Out

1:15-1:22: Unexpected emphasis marker `_`, expected `*`

not-ok.md

When configured with '🌍'.

Out

1:1: Unexpected value `🌍` for `options`, expected `'*'`, `'_'`, or `'consistent'`

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-emphasis-marker@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