hast-util-from-html-isomorphic

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[hast][] utility that turns HTML into a syntax tree, using browser APIs
when available, so it has a smaller bundle size there.

* What is this?
* When should I use this?
* Install
* Use
* API
* [fromHtmlIsomorphic(value[, options])](#fromhtmlisomorphicvalue-options)
* Options
* Examples
* Example: fragment versus document
* Syntax
* Types
* Compatibility
* Security
* Related
* Contribute
* License

What is this?

This package is a utility that takes HTML input and turns it into a hast syntax
tree.

In a browser, this uses [hast-util-from-dom][hast-util-from-dom],
otherwise it uses [hast-util-from-html][hast-util-from-html].

When should I use this?

If you want to get a syntax tree without positional info, and your code should
be isomorphic (it could run anywhere), as it results in a smaller bundle size.

If you need positional information, use
[hast-util-from-html][hast-util-from-html].

If you don’t care about positional info and your code only runs in browsers,
use [hast-util-from-dom][hast-util-from-dom].

Finally you can use the utility [hast-util-to-html][hast-util-to-html],
or [hast-util-to-dom][hast-util-to-dom] with .outerHTML, to do the inverse
of this utility.
That turns hast into HTML.

Install

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

``sh npm install hast-util-from-html-isomorphic`

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

`js import {fromHtmlIsomorphic} from 'https://esm.sh/hast-util-from-html-isomorphic@2'`

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

`html`

`Use`

`js import {fromHtmlIsomorphic} from 'hast-util-from-html-isomorphic'

const tree = fromHtmlIsomorphic('

`Hello, world!`

', {fragment: true})

console.log(tree)`

Yields (positional info and data omitted for brevity):

`js { type: 'root', children: [ { type: 'element', tagName: 'h1', properties: {}, children: [Array], } ] }`

`API`

This package exports the identifier [fromHtmlIsomorphic][api-from-html-isomorphic]. There is no default export.

`$3`

Turn serialized HTML into a hast tree.

###### Parameters

* value (string) — serialized HTML to parse *options ([Options][api-options], optional) — configuration

###### Returns

Tree ([Root][root]).

`$3`

Configuration (TypeScript type).

##### Fields

###### fragment

Whether to parse as a fragment (boolean, default: false). The default is to expect a whole document. In document mode, unopenedhtml, head, and body elements are opened.

`Examples`

`$3`

The following example shows the difference between parsing as a document and parsing as a fragment:

`js import {fromHtml} from 'hast-util-from-html-isomorphic'

const doc = 'Hi!

`Hello!`

'
console.log(fromHtml(doc))

console.log(fromHtml(doc, {fragment: true}))`

…yields (positional info and data omitted for brevity):

`js { type: 'root', children: [ {type: 'element', tagName: 'html', properties: {}, children: [Array]} ] }`

`js { type: 'root', children: [ {type: 'element', tagName: 'title', properties: {}, children: [Array]}, {type: 'element', tagName: 'h1', properties: {}, children: [Array]} ] }`

> 👉 Note: observe that when a whole document is expected (first example), > missing elements are opened and closed.

`Syntax`

HTML is parsed according to WHATWG HTML (the living standard), which is also followed by browsers such as Chrome and Firefox.

`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,hast-util-from-html-isomorphic@^1, compatible with Node.js 16.

`Security`

Parsing HTML is safe but using user-provided content can open you up to a [cross-site scripting (XSS)][xss] attack. Use [hast-util-santize][hast-util-sanitize] to make the hast tree safe.

`Related`

* hast-util-from-html— parse html into hast *hast-util-from-dom— parse a DOM tree into hast *hast-util-to-html— serialize hast *hast-util-sanitize— sanitize hast * [xast-util-from-xml][xast-util-from-xml] — parse XML

`Contribute`

See [contributing.md][contributing] in [syntax-tree/.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] © [Remco Haszing][author]

[build-badge]: https://github.com/syntax-tree/hast-util-from-html-isomorphic/workflows/main/badge.svg

[build]: https://github.com/syntax-tree/hast-util-from-html-isomorphic/actions

[coverage-badge]: https://img.shields.io/codecov/c/github/syntax-tree/hast-util-from-html-isomorphic.svg

[coverage]: https://codecov.io/github/syntax-tree/hast-util-from-html-isomorphic

[downloads-badge]: https://img.shields.io/npm/dm/hast-util-from-html-isomorphic.svg

[downloads]: https://www.npmjs.com/package/hast-util-from-html-isomorphic

[size-badge]: https://img.shields.io/badge/dynamic/json?label=minzipped%20size&query=$.size.compressedSize&url=https://deno.bundlejs.com/?q=hast-util-from-html-isomorphic

[size]: https://bundlejs.com/?q=hast-util-from-html-isomorphic

[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/syntax-tree/unist/discussions

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

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

[esmsh]: https://esm.sh

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

[license]: license

[author]: https://github.com/remcohaszing

[health]: https://github.com/syntax-tree/.github

[contributing]: https://github.com/syntax-tree/.github/blob/main/contributing.md

[support]: https://github.com/syntax-tree/.github/blob/main/support.md

[coc]: https://github.com/syntax-tree/.github/blob/main/code-of-conduct.md

[xss]: https://en.wikipedia.org/wiki/Cross-site_scripting

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

[root]: https://github.com/syntax-tree/hast#root

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

[hast-util-from-dom]: https://github.com/syntax-tree/hast-util-from-dom

[hast-util-from-html]: https://github.com/syntax-tree/hast-util-from-html

[hast-util-to-dom]: https://github.com/syntax-tree/hast-util-to-dom

[hast-util-to-html]: https://github.com/syntax-tree/hast-util-to-html

[xast-util-from-xml]: https://github.com/syntax-tree/xast-util-from-xml

[api-from-html-isomorphic]: #fromhtmlisomorphicvalue-options

[api-options]: #options

hast-util-from-html-isomorphic

[hast][] utility that turns HTML into a syntax tree, using browser APIs
when available, so it has a smaller bundle size there.

What is this?

This package is a utility that takes HTML input and turns it into a hast syntax
tree.

In a browser, this uses [hast-util-from-dom][hast-util-from-dom],
otherwise it uses [hast-util-from-html][hast-util-from-html].

When should I use this?

If you want to get a syntax tree without positional info, and your code should
be isomorphic (it could run anywhere), as it results in a smaller bundle size.

If you need positional information, use
[hast-util-from-html][hast-util-from-html].

If you don’t care about positional info and your code only runs in browsers,
use [hast-util-from-dom][hast-util-from-dom].

Finally you can use the utility [hast-util-to-html][hast-util-to-html],
or [hast-util-to-dom][hast-util-to-dom] with .outerHTML, to do the inverse
of this utility.
That turns hast into HTML.

Install

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

``sh npm install hast-util-from-html-isomorphic`

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

`js import {fromHtmlIsomorphic} from 'https://esm.sh/hast-util-from-html-isomorphic@2'`

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

`html`

`Use`

`js import {fromHtmlIsomorphic} from 'hast-util-from-html-isomorphic'

const tree = fromHtmlIsomorphic('

`Hello, world!`

', {fragment: true})

console.log(tree)`

Yields (positional info and data omitted for brevity):

`js { type: 'root', children: [ { type: 'element', tagName: 'h1', properties: {}, children: [Array], } ] }`

`API`

This package exports the identifier [fromHtmlIsomorphic][api-from-html-isomorphic]. There is no default export.

`$3`

Turn serialized HTML into a hast tree.

###### Parameters

* value (string) — serialized HTML to parse *options ([Options][api-options], optional) — configuration

###### Returns

Tree ([Root][root]).

`$3`

Configuration (TypeScript type).

##### Fields

###### fragment

Whether to parse as a fragment (boolean, default: false). The default is to expect a whole document. In document mode, unopenedhtml, head, and body elements are opened.

`Examples`

`$3`

The following example shows the difference between parsing as a document and parsing as a fragment:

`js import {fromHtml} from 'hast-util-from-html-isomorphic'

const doc = 'Hi!

`Hello!`

'
console.log(fromHtml(doc))