562 lines
31 KiB
Markdown
562 lines
31 KiB
Markdown
# rehype-parse
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[![Build][build-badge]][build]
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[![Coverage][coverage-badge]][coverage]
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[![Downloads][downloads-badge]][downloads]
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[![Size][size-badge]][size]
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[![Backers][backers-badge]][collective]
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[![Chat][chat-badge]][chat]
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**[rehype][]** plugin to add support for parsing HTML input.
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## Contents
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* [What is this?](#what-is-this)
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* [When should I use this?](#when-should-i-use-this)
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* [Install](#install)
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* [Use](#use)
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* [API](#api)
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* [`unified().use(rehypeParse[, options])`](#unifieduserehypeparse-options)
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* [Examples](#examples)
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* [Example: fragment versus document](#example-fragment-versus-document)
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* [Example: whitespace around and inside `<html>`](#example-whitespace-around-and-inside-html)
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* [Example: parse errors](#example-parse-errors)
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* [Syntax](#syntax)
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* [Syntax tree](#syntax-tree)
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* [Types](#types)
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* [Compatibility](#compatibility)
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* [Security](#security)
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* [Contribute](#contribute)
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* [Sponsor](#sponsor)
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* [License](#license)
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## What is this?
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This package is a [unified][] ([rehype][]) plugin that defines how to take HTML
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as input and turn it into a syntax tree.
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When it’s used, HTML can be parsed and other rehype plugins can be used after
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it.
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See [the monorepo readme][rehype] for info on what the rehype ecosystem is.
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## When should I use this?
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This plugin adds support to unified for parsing HTML.
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You can alternatively use [`rehype`][rehype-core] instead, which combines
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unified, this plugin, and [`rehype-stringify`][rehype-stringify].
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When you’re in a browser, trust your content, don’t need positional info, and
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value a smaller bundle size, you can use [`rehype-dom-parse`][rehype-dom-parse]
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instead.
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This plugin is built on [`parse5`][parse5] and
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[`hast-util-from-parse5`][hast-util-from-parse5], which deal with HTML-compliant
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tokenizing, parsing, and creating nodes.
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rehype focusses on making it easier to transform content by abstracting such
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internals away.
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## Install
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This package is [ESM only][esm].
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In Node.js (version 12.20+, 14.14+, or 16.0+), install with [npm][]:
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```sh
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npm install rehype-parse
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```
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In Deno with [Skypack][]:
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```js
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import rehypeParse from 'https://cdn.skypack.dev/rehype-parse@8?dts'
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```
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In browsers with [Skypack][]:
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```html
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<script type="module">
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import rehypeParse from 'https://cdn.skypack.dev/rehype-parse@8?min'
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</script>
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```
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## Use
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Say we have the following module `example.js`:
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```js
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import {unified} from 'unified'
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import rehypeParse from 'rehype-parse'
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import rehypeRemark from 'rehype-remark'
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import remarkStringify from 'remark-stringify'
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main()
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async function main() {
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const file = await unified()
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.use(rehypeParse)
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.use(rehypeRemark)
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.use(remarkStringify)
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.process('<h1>Hello, world!</h1>')
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console.log(String(file))
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}
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```
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…running that with `node example.js` yields:
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```markdown
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# Hello, world!
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```
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## API
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This package exports no identifiers.
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The default export is `rehypeParse`.
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### `unified().use(rehypeParse[, options])`
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Add support for parsing HTML input.
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##### `options`
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Configuration (optional).
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###### `options.fragment`
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Specify whether to parse as a fragment (`boolean`, default: `false`).
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The default is to expect a whole document.
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In document mode, unopened `html`, `head`, and `body` elements are opened.
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###### `options.space`
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Which space the document is in (`'svg'` or `'html'`, default: `'html'`).
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When an `<svg>` element is found in the HTML space, `rehype-parse` already
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automatically switches to and from the SVG space when entering and exiting it.
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> 👉 **Note**: rehype is not an XML parser.
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> It supports SVG as embedded in HTML.
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> It does not support the features available in XML.
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> Passing SVG files might break but fragments of modern SVG should be fine.
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> 👉 **Note**: make sure to set `fragment: true` if `space: 'svg'`.
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###### `options.emitParseErrors`
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Emit [HTML parse errors][parse-errors] as warning messages
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(`boolean`, default: `false`).
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Specific rules can be turned off by setting their IDs in `options` to `false`
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(or `0`).
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The default, when `emitParseErrors: true`, is `true` (or `1`), and means that
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rules emit as warnings.
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Rules can also be configured with `2`, to turn them into fatal errors.
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The list of parse errors:
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<!-- parse-error start -->
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* `abandonedHeadElementChild` — unexpected metadata element after head ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/abandoned-head-element-child/index.html))
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* [`abruptClosingOfEmptyComment`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-abrupt-closing-of-empty-comment) — unexpected abruptly closed empty comment ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/abrupt-closing-of-empty-comment/index.html))
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* [`abruptDoctypePublicIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-abrupt-doctype-public-identifier) — unexpected abruptly closed public identifier ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/abrupt-doctype-public-identifier/index.html))
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* [`abruptDoctypeSystemIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-abrupt-doctype-system-identifier) — unexpected abruptly closed system identifier ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/abrupt-doctype-system-identifier/index.html))
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* [`absenceOfDigitsInNumericCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-absence-of-digits-in-numeric-character-reference) — unexpected non-digit at start of numeric character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/absence-of-digits-in-numeric-character-reference/index.html))
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* [`cdataInHtmlContent`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-cdata-in-html-content) — unexpected CDATA section in HTML ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/cdata-in-html-content/index.html))
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* [`characterReferenceOutsideUnicodeRange`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-character-reference-outside-unicode-range) — unexpected too big numeric character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/character-reference-outside-unicode-range/index.html))
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* `closingOfElementWithOpenChildElements` — unexpected closing tag with open child elements ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/closing-of-element-with-open-child-elements/index.html))
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* [`controlCharacterInInputStream`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-control-character-in-input-stream) — unexpected control character ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/control-character-in-input-stream/index.html))
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* [`controlCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-control-character-reference) — unexpected control character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/control-character-reference/index.html))
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* `disallowedContentInNoscriptInHead` — disallowed content inside `<noscript>` in `<head>` ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/disallowed-content-in-noscript-in-head/index.html))
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* [`duplicateAttribute`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-duplicate-attribute) — unexpected duplicate attribute ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/duplicate-attribute/index.html))
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* [`endTagWithAttributes`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-end-tag-with-attributes) — unexpected attribute on closing tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/end-tag-with-attributes/index.html))
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* [`endTagWithTrailingSolidus`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-end-tag-with-trailing-solidus) — unexpected slash at end of closing tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/end-tag-with-trailing-solidus/index.html))
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* `endTagWithoutMatchingOpenElement` — unexpected unopened end tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/end-tag-without-matching-open-element/index.html))
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* [`eofBeforeTagName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-eof-before-tag-name) — unexpected end of file ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-before-tag-name/index.html))
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* [`eofInCdata`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-eof-in-cdata) — unexpected end of file in CDATA ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-in-cdata/index.html))
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* [`eofInComment`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-eof-in-comment) — unexpected end of file in comment ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-in-comment/index.html))
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* [`eofInDoctype`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-eof-in-doctype) — unexpected end of file in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-in-doctype/index.html))
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* `eofInElementThatCanContainOnlyText` — unexpected end of file in element that can only contain text ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-in-element-that-can-contain-only-text/index.html))
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* [`eofInScriptHtmlCommentLikeText`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-eof-in-script-html-comment-like-text) — unexpected end of file in comment inside script ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-in-script-html-comment-like-text/index.html))
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* [`eofInTag`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-eof-in-tag) — unexpected end of file in tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/eof-in-tag/index.html))
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* [`incorrectlyClosedComment`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-incorrectly-closed-comment) — incorrectly closed comment ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/incorrectly-closed-comment/index.html))
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* [`incorrectlyOpenedComment`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-incorrectly-opened-comment) — incorrectly opened comment ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/incorrectly-opened-comment/index.html))
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* [`invalidCharacterSequenceAfterDoctypeName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-invalid-character-sequence-after-doctype-name) — invalid sequence after doctype name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/invalid-character-sequence-after-doctype-name/index.html))
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* [`invalidFirstCharacterOfTagName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-invalid-first-character-of-tag-name) — invalid first character in tag name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/invalid-first-character-of-tag-name/index.html))
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* `misplacedDoctype` — misplaced doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/misplaced-doctype/index.html))
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* `misplacedStartTagForHeadElement` — misplaced `<head>` start tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/misplaced-start-tag-for-head-element/index.html))
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* [`missingAttributeValue`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-attribute-value) — missing attribute value ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-attribute-value/index.html))
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* `missingDoctype` — missing doctype before other content ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-doctype/index.html))
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* [`missingDoctypeName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-doctype-name) — missing doctype name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-doctype-name/index.html))
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* [`missingDoctypePublicIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-doctype-public-identifier) — missing public identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-doctype-public-identifier/index.html))
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* [`missingDoctypeSystemIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-doctype-system-identifier) — missing system identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-doctype-system-identifier/index.html))
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* [`missingEndTagName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-end-tag-name) — missing name in end tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-end-tag-name/index.html))
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* [`missingQuoteBeforeDoctypePublicIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-quote-before-doctype-public-identifier) — missing quote before public identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-quote-before-doctype-public-identifier/index.html))
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* [`missingQuoteBeforeDoctypeSystemIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-quote-before-doctype-system-identifier) — missing quote before system identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-quote-before-doctype-system-identifier/index.html))
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* [`missingSemicolonAfterCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-semicolon-after-character-reference) — missing semicolon after character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-semicolon-after-character-reference/index.html))
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* [`missingWhitespaceAfterDoctypePublicKeyword`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-whitespace-after-doctype-public-keyword) — missing whitespace after public identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-whitespace-after-doctype-public-keyword/index.html))
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* [`missingWhitespaceAfterDoctypeSystemKeyword`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-whitespace-after-doctype-system-keyword) — missing whitespace after system identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-whitespace-after-doctype-system-keyword/index.html))
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* [`missingWhitespaceBeforeDoctypeName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-whitespace-before-doctype-name) — missing whitespace before doctype name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-whitespace-before-doctype-name/index.html))
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* [`missingWhitespaceBetweenAttributes`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-whitespace-between-attributes) — missing whitespace between attributes ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-whitespace-between-attributes/index.html))
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* [`missingWhitespaceBetweenDoctypePublicAndSystemIdentifiers`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-missing-whitespace-between-doctype-public-and-system-identifiers) — missing whitespace between public and system identifiers in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/missing-whitespace-between-doctype-public-and-system-identifiers/index.html))
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* [`nestedComment`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-nested-comment) — unexpected nested comment ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/nested-comment/index.html))
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* `nestedNoscriptInHead` — unexpected nested `<noscript>` in `<head>` ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/nested-noscript-in-head/index.html))
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* `nonConformingDoctype` — unexpected non-conforming doctype declaration ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/non-conforming-doctype/index.html))
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* [`nonVoidHtmlElementStartTagWithTrailingSolidus`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-non-void-html-element-start-tag-with-trailing-solidus) — unexpected trailing slash on start tag of non-void element ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/non-void-html-element-start-tag-with-trailing-solidus/index.html))
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* [`noncharacterCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-noncharacter-character-reference) — unexpected noncharacter code point referenced by character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/noncharacter-character-reference/index.html))
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* [`noncharacterInInputStream`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-noncharacter-in-input-stream) — unexpected noncharacter character ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/noncharacter-in-input-stream/index.html))
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* [`nullCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-null-character-reference) — unexpected NULL character referenced by character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/null-character-reference/index.html))
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* `openElementsLeftAfterEof` — unexpected end of file ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/open-elements-left-after-eof/index.html))
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* [`surrogateCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-surrogate-character-reference) — unexpected surrogate character referenced by character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/surrogate-character-reference/index.html))
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* [`surrogateInInputStream`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-surrogate-in-input-stream) — unexpected surrogate character
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* [`unexpectedCharacterAfterDoctypeSystemIdentifier`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-character-after-doctype-system-identifier) — invalid character after system identifier in doctype ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-character-after-doctype-system-identifier/index.html))
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* [`unexpectedCharacterInAttributeName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-character-in-attribute-name) — unexpected character in attribute name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-character-in-attribute-name/index.html))
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* [`unexpectedCharacterInUnquotedAttributeValue`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-character-in-unquoted-attribute-value) — unexpected character in unquoted attribute value ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-character-in-unquoted-attribute-value/index.html))
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* [`unexpectedEqualsSignBeforeAttributeName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-equals-sign-before-attribute-name) — unexpected equals sign before attribute name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-equals-sign-before-attribute-name/index.html))
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* [`unexpectedNullCharacter`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-null-character) — unexpected NULL character ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-null-character/index.html))
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* [`unexpectedQuestionMarkInsteadOfTagName`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-question-mark-instead-of-tag-name) — unexpected question mark instead of tag name ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-question-mark-instead-of-tag-name/index.html))
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* [`unexpectedSolidusInTag`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unexpected-solidus-in-tag) — unexpected slash in tag ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unexpected-solidus-in-tag/index.html))
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* [`unknownNamedCharacterReference`](https://html.spec.whatwg.org/multipage/parsing.html#parse-error-unknown-named-character-reference) — unexpected unknown named character reference ([example](https://github.com/rehypejs/rehype/blob/main/test/parse-error/unknown-named-character-reference/index.html))
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<!-- parse-error end -->
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###### `options.verbose`
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Add extra positional info (`boolean`, default: `false`).
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|
||
## Examples
|
||
|
||
### Example: fragment versus document
|
||
|
||
The following example shows the difference between parsing as a document and
|
||
parsing as a fragment:
|
||
|
||
```js
|
||
import {unified} from 'unified'
|
||
import rehypeParse from 'rehype-parse'
|
||
import rehypeStringify from 'rehype-stringify'
|
||
|
||
main()
|
||
|
||
async function main() {
|
||
const doc = '<title>Hi!</title><h1>Hello!</h1>'
|
||
|
||
console.log(
|
||
String(
|
||
await unified()
|
||
.use(rehypeParse, {fragment: true})
|
||
.use(rehypeStringify)
|
||
.process(doc)
|
||
)
|
||
)
|
||
|
||
console.log(
|
||
String(
|
||
await unified()
|
||
.use(rehypeParse, {fragment: false})
|
||
.use(rehypeStringify)
|
||
.process(doc)
|
||
)
|
||
)
|
||
}
|
||
```
|
||
|
||
…yields:
|
||
|
||
```html
|
||
<title>Hi!</title><h1>Hello!</h1>
|
||
```
|
||
|
||
```html
|
||
<html><head><title>Hi!</title></head><body><h1>Hello!</h1></body></html>
|
||
```
|
||
|
||
> 👉 **Note**: observe that when a whole document is expected (second example),
|
||
> missing elements are opened and closed.
|
||
|
||
### Example: whitespace around and inside `<html>`
|
||
|
||
The following example shows how whitespace is handled when around and directly
|
||
inside the `<html>` element:
|
||
|
||
```js
|
||
import {unified} from 'unified'
|
||
import rehypeParse from 'rehype-parse'
|
||
import rehypeStringify from 'rehype-stringify'
|
||
|
||
main(`<!doctype html>
|
||
<html lang=en>
|
||
<head>
|
||
<title>Hi!</title>
|
||
</head>
|
||
<body>
|
||
<h1>Hello!</h1>
|
||
</body>
|
||
</html>`)
|
||
|
||
async function main(doc) {
|
||
console.log(
|
||
String(await unified().use(rehypeParse).use(rehypeStringify).process(doc))
|
||
)
|
||
}
|
||
```
|
||
|
||
…yields (where `␠` represents a space character):
|
||
|
||
```html
|
||
<!doctype html><html lang="en"><head>
|
||
<title>Hi!</title>
|
||
</head>
|
||
<body>
|
||
<h1>Hello!</h1>
|
||
␠␠
|
||
</body></html>
|
||
```
|
||
|
||
> 👉 **Note**: observe that the line ending before `<html>` is ignored, the line
|
||
> ending and two spaces before `<head>` is moved inside it, and the line ending
|
||
> after `</body>` is moved before it.
|
||
|
||
This behavior is described by the HTML standard (see the section 13.2.6.4.1
|
||
“The ‘initial’ insertion mode” and adjacent states) which rehype follows.
|
||
|
||
The changes to this meaningless whitespace should not matter, except when
|
||
formatting markup, in which case [`rehype-format`][rehype-format] can be used to
|
||
improve the source code.
|
||
|
||
### Example: parse errors
|
||
|
||
The following example shows how HTML parse errors can be enabled and configured:
|
||
|
||
```js
|
||
import {reporter} from 'vfile-reporter'
|
||
import {unified} from 'unified'
|
||
import rehypeParse from 'rehype-parse'
|
||
import rehypeStringify from 'rehype-stringify'
|
||
|
||
main()
|
||
|
||
async function main() {
|
||
const file = await unified()
|
||
.use(rehypeParse, {
|
||
emitParseErrors: true, // Emit all.
|
||
missingWhitespaceBeforeDoctypeName: 2, // Mark one as a fatal error.
|
||
nonVoidHtmlElementStartTagWithTrailingSolidus: false // Ignore one.
|
||
})
|
||
.use(rehypeStringify)
|
||
.process(`<!doctypehtml>
|
||
<title class="a" class="b">Hello…</title>
|
||
<h1/>World!</h1>`)
|
||
|
||
console.log(reporter(file))
|
||
}
|
||
```
|
||
|
||
…yields:
|
||
|
||
```html
|
||
1:10-1:10 error Missing whitespace before doctype name missing-whitespace-before-doctype-name parse-error
|
||
2:23-2:23 warning Unexpected duplicate attribute duplicate-attribute parse-error
|
||
|
||
2 messages (✖ 1 error, ⚠ 1 warning)
|
||
```
|
||
|
||
> 🧑🏫 **Info**: messages in unified are warnings instead of errors.
|
||
> Other linters (such as ESLint) almost always use errors.
|
||
> Why?
|
||
> Those tools *only* check code style.
|
||
> They don’t generate, transform, and format code, which is what rehype and
|
||
> unified focus on, too.
|
||
> Errors in unified mean the same as an exception in your JavaScript code: a
|
||
> crash.
|
||
> That’s why we use warnings instead, because we continue checking more HTML and
|
||
> continue running more plugins.
|
||
|
||
## Syntax
|
||
|
||
HTML is parsed according to WHATWG HTML (the living standard), which is also
|
||
followed by browsers such as Chrome and Firefox.
|
||
|
||
## Syntax tree
|
||
|
||
The syntax tree format used in rehype is [hast][].
|
||
|
||
## Types
|
||
|
||
This package is fully typed with [TypeScript][].
|
||
The extra types `Options`, `ErrorCode`, and `ErrorSeverity` are exported.
|
||
|
||
## Compatibility
|
||
|
||
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.
|
||
|
||
## Security
|
||
|
||
As **rehype** works on HTML, and improper use of HTML can open you up to a
|
||
[cross-site scripting (XSS)][xss] attack, use of rehype can also be unsafe.
|
||
Use [`rehype-sanitize`][rehype-sanitize] to make the tree safe.
|
||
|
||
Use of rehype plugins could also open you up to other attacks.
|
||
Carefully assess each plugin and the risks involved in using them.
|
||
|
||
For info on how to submit a report, see our [security policy][security].
|
||
|
||
## 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.
|
||
|
||
## Sponsor
|
||
|
||
Support this effort and give back by sponsoring on [OpenCollective][collective]!
|
||
|
||
<!--lint ignore no-html-->
|
||
|
||
<table>
|
||
<tr valign="middle">
|
||
<td width="20%" align="center" rowspan="2" colspan="2">
|
||
<a href="https://vercel.com">Vercel</a><br><br>
|
||
<a href="https://vercel.com"><img src="https://avatars1.githubusercontent.com/u/14985020?s=256&v=4" width="128"></a>
|
||
</td>
|
||
<td width="20%" align="center" rowspan="2" colspan="2">
|
||
<a href="https://motif.land">Motif</a><br><br>
|
||
<a href="https://motif.land"><img src="https://avatars1.githubusercontent.com/u/74457950?s=256&v=4" width="128"></a>
|
||
</td>
|
||
<td width="20%" align="center" rowspan="2" colspan="2">
|
||
<a href="https://www.hashicorp.com">HashiCorp</a><br><br>
|
||
<a href="https://www.hashicorp.com"><img src="https://avatars1.githubusercontent.com/u/761456?s=256&v=4" width="128"></a>
|
||
</td>
|
||
<td width="20%" align="center" rowspan="2" colspan="2">
|
||
<a href="https://www.gitbook.com">GitBook</a><br><br>
|
||
<a href="https://www.gitbook.com"><img src="https://avatars1.githubusercontent.com/u/7111340?s=256&v=4" width="128"></a>
|
||
</td>
|
||
<td width="20%" align="center" rowspan="2" colspan="2">
|
||
<a href="https://www.gatsbyjs.org">Gatsby</a><br><br>
|
||
<a href="https://www.gatsbyjs.org"><img src="https://avatars1.githubusercontent.com/u/12551863?s=256&v=4" width="128"></a>
|
||
</td>
|
||
</tr>
|
||
<tr valign="middle">
|
||
</tr>
|
||
<tr valign="middle">
|
||
<td width="20%" align="center" rowspan="2" colspan="2">
|
||
<a href="https://www.netlify.com">Netlify</a><br><br>
|
||
<!--OC has a sharper image-->
|
||
<a href="https://www.netlify.com"><img src="https://images.opencollective.com/netlify/4087de2/logo/256.png" width="128"></a>
|
||
</td>
|
||
<td width="10%" align="center">
|
||
<a href="https://www.coinbase.com">Coinbase</a><br><br>
|
||
<a href="https://www.coinbase.com"><img src="https://avatars1.githubusercontent.com/u/1885080?s=256&v=4" width="64"></a>
|
||
</td>
|
||
<td width="10%" align="center">
|
||
<a href="https://themeisle.com">ThemeIsle</a><br><br>
|
||
<a href="https://themeisle.com"><img src="https://avatars1.githubusercontent.com/u/58979018?s=128&v=4" width="64"></a>
|
||
</td>
|
||
<td width="10%" align="center">
|
||
<a href="https://expo.io">Expo</a><br><br>
|
||
<a href="https://expo.io"><img src="https://avatars1.githubusercontent.com/u/12504344?s=128&v=4" width="64"></a>
|
||
</td>
|
||
<td width="10%" align="center">
|
||
<a href="https://boostnote.io">Boost Note</a><br><br>
|
||
<a href="https://boostnote.io"><img src="https://images.opencollective.com/boosthub/6318083/logo/128.png" width="64"></a>
|
||
</td>
|
||
<td width="10%" align="center">
|
||
<a href="https://www.holloway.com">Holloway</a><br><br>
|
||
<a href="https://www.holloway.com"><img src="https://avatars1.githubusercontent.com/u/35904294?s=128&v=4" width="64"></a>
|
||
</td>
|
||
<td width="10%"></td>
|
||
<td width="10%"></td>
|
||
<td width="10%"></td>
|
||
</tr>
|
||
<tr valign="middle">
|
||
<td width="100%" align="center" colspan="8">
|
||
<br>
|
||
<a href="https://opencollective.com/unified"><strong>You?</strong></a>
|
||
<br><br>
|
||
</td>
|
||
</tr>
|
||
</table>
|
||
|
||
## License
|
||
|
||
[MIT][license] © [Titus Wormer][author]
|
||
|
||
<!-- Definitions -->
|
||
|
||
[build-badge]: https://github.com/rehypejs/rehype/workflows/main/badge.svg
|
||
|
||
[build]: https://github.com/rehypejs/rehype/actions
|
||
|
||
[coverage-badge]: https://img.shields.io/codecov/c/github/rehypejs/rehype.svg
|
||
|
||
[coverage]: https://codecov.io/github/rehypejs/rehype
|
||
|
||
[downloads-badge]: https://img.shields.io/npm/dm/rehype-parse.svg
|
||
|
||
[downloads]: https://www.npmjs.com/package/rehype-parse
|
||
|
||
[size-badge]: https://img.shields.io/bundlephobia/minzip/rehype-parse.svg
|
||
|
||
[size]: https://bundlephobia.com/result?p=rehype-parse
|
||
|
||
[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
|
||
|
||
[security]: https://github.com/rehypejs/.github/blob/main/security.md
|
||
|
||
[health]: https://github.com/rehypejs/.github
|
||
|
||
[contributing]: https://github.com/rehypejs/.github/blob/main/contributing.md
|
||
|
||
[support]: https://github.com/rehypejs/.github/blob/main/support.md
|
||
|
||
[coc]: https://github.com/rehypejs/.github/blob/main/code-of-conduct.md
|
||
|
||
[license]: https://github.com/rehypejs/rehype/blob/main/license
|
||
|
||
[author]: https://wooorm.com
|
||
|
||
[esm]: https://gist.github.com/sindresorhus/a39789f98801d908bbc7ff3ecc99d99c
|
||
|
||
[npm]: https://docs.npmjs.com/cli/install
|
||
|
||
[skypack]: https://www.skypack.dev
|
||
|
||
[unified]: https://github.com/unifiedjs/unified
|
||
|
||
[rehype]: https://github.com/rehypejs/rehype
|
||
|
||
[hast]: https://github.com/syntax-tree/hast
|
||
|
||
[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting
|
||
|
||
[typescript]: https://www.typescriptlang.org
|
||
|
||
[rehype-stringify]: ../rehype-stringify/
|
||
|
||
[rehype-core]: ../rehype/
|
||
|
||
[rehype-sanitize]: https://github.com/rehypejs/rehype-sanitize
|
||
|
||
[hast-util-from-parse5]: https://github.com/syntax-tree/hast-util-from-parse5
|
||
|
||
[parse-errors]: https://html.spec.whatwg.org/multipage/parsing.html#parse-errors
|
||
|
||
[rehype-dom-parse]: https://github.com/rehypejs/rehype-dom/tree/main/packages/rehype-dom-parse
|
||
|
||
[rehype-format]: https://github.com/rehypejs/rehype-format
|
||
|
||
[parse5]: https://github.com/inikulin/parse5
|