hast-util-from-dom

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[hast][] utility to transform from a [DOM][] tree.

Contents

* What is this?
* When should I use this?
* Install
* Use
* API
* fromDom(tree, options?)
* AfterTransform
* Options
* Types
* Compatibility
* Security
* Contribute
* Related
* License

What is this?

This package is a utility that takes a DOM tree (from the actual DOM or from
things like [jsdom][jsdom]) as input and turns it into a [hast][] (HTML)
syntax tree.

When should I use this?

You can use this project when you want to use hast in browsers.
This package is very small, but it does so by:

* …not providing positional information
* …potentially yielding varying results in different (especially older)
browsers

The hast utility [hast-util-to-dom][hast-util-to-dom] does the inverse of this
utility.
It turns hast into a DOM tree.

The rehype plugin [rehype-dom-parse][rehype-dom-parse] wraps this utility to
parse HTML with DOM APIs.

Install

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

``sh
npm install hast-util-from-dom
`

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

`js
import {fromDom} from 'https://esm.sh/hast-util-from-dom@5'
`

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

`html

`

Use

Say our page example.html looks as follows:

`html





Hi

Hello, world!



`

Now running open example.html prints the following to the console:

`js
{type: "element", tagName: "main", properties: {}, children: Array}
`

API

This package exports the identifier [fromDom][api-from-dom].
There is no default export.

$3

Transform a DOM tree to a hast tree.

###### Parameters

* tree ([DomNode][dom-node])
— DOM tree to transform
* options ([Options][api-options], optional)
— configuration

###### Returns

Equivalent hast node ([HastNode][hast-node]).

$3

Callback called when each node is transformed (TypeScript type).

###### Parameters

* domNode ([DomNode][dom-node])
— DOM node that was handled
* hastNode ([HastNode][hast-node])
— corresponding hast node

###### Returns

Nothing.

$3

Configuration (TypeScript type).

##### Fields

* afterTransform ([AfterTransform][api-after-transform], optional)
— callback called when each node is transformed

##### Returns

[HastNode][hast-node].

Types

This package is fully typed with [TypeScript][].
It exports the additional types [AfterTransform][api-after-transform] and
[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-dom@^5,
compatible with Node.js 16.

Security

Use of hast-util-from-dom itself is safe but see other utilities for more
information on potential security problems.

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, organisation, or community you agree to
abide by its terms.

Related

* [hast-util-from-html][hast-util-from-html]
— parse hast from a string of HTML
* hast-util-sanitize
— sanitize hast nodes
* hast-util-to-html
— serialize hast as HTML
* hast-util-to-dom`
— create DOM trees from hast

License

[ISC][license] © [Keith McKnight][author]

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

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

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[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://keith.mcknig.ht

[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

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

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

[dom]: https://developer.mozilla.org/docs/Web/API/Document_Object_Model

[dom-node]: https://developer.mozilla.org/docs/Web/API/Node

[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

[rehype-dom-parse]: https://github.com/rehypejs/rehype-dom/tree/main/packages/rehype-dom-parse

[jsdom]: https://github.com/jsdom/jsdom

[api-from-dom]: #fromdomtree-options

[api-options]: #options

[api-after-transform]: #aftertransform