unist-util-find-before

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[unist][] utility to find a node before another node.

Contents

* What is this?
* When should I use this?
* Install
* Use
* API
* [findBefore(parent, node|index[, test])](#findbeforeparent-nodeindex-test)
* Types
* Compatibility
* Related
* Contribute
* License

What is this?

This is a tiny utility that you can use to find a node before another node or
before an index in a parent.

When should I use this?

This is super tiny.
You can of course do it yourself.
But this helps when integrating with the rest of unified and unist.

Install

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

``sh
npm install unist-util-find-before
`

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

`js
import {findBefore} from 'https://esm.sh/unist-util-find-before@4'
`

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

`html

`

Use

`js
import {u} from 'unist-builder'
import {findBefore} from 'unist-util-find-before'

const tree = u('tree', [
u('leaf', 'leaf 1'),
u('parent', [u('leaf', 'leaf 2'), u('leaf', 'leaf 3')]),
u('leaf', 'leaf 4'),
u('parent', [u('leaf', 'leaf 5')]),
u('leaf', 'leaf 6'),
u('empty'),
u('leaf', 'leaf 7')
])

const empty = tree.children[5]

console.log(findBefore(tree, empty, 'parent'))
`

Yields:

`js
{type: 'parent', children: [{type: 'leaf', value: 'leaf 5'}]}
`

API

This package exports the identifier [findBefore][api-findbefore].
There is no default export.

$3

Find the first node in parent before another node or before an index,
that passes test.

###### Parameters

* parent ([Node][node])
— parent node
* index (number)
— index of child in parent
* child ([Node][node])
— child in parent
* test ([Test][test])
— unist-util-is-compatible test

###### Returns

Child of parent ([Node][node]) or undefined.

Types

This package is fully typed with [TypeScript][].
It exports no additional types (types for the test are in unist-util-is).

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, unist-util-find-before@^4,
compatible with Node.js 16.

Related

* unist-util-find-after
— find a node after another node
* unist-util-find-all-after
— find all nodes after another node
* unist-util-find-all-before
— find all nodes before another node
* unist-util-find-all-between
— find all nodes between two nodes
* unist-util-visit
— walk the tree
* unist-util-visit-parents
— walk the tree with a stack of parents
* unist-util-filter
— create a new tree with all nodes that pass a test
* unist-util-map
— create a new tree with all nodes mapped by a given function
* unist-util-flatmap
— create a new tree by mapping (to an array) by a given function
* unist-util-remove
— remove nodes from a tree that pass a test
* unist-util-select
— select nodes with CSS-like selectors

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.

License

[MIT][license] © [Titus Wormer][author]

[build-badge]: https://github.com/syntax-tree/unist-util-find-before/workflows/main/badge.svg

[build]: https://github.com/syntax-tree/unist-util-find-before/actions

[coverage-badge]: https://img.shields.io/codecov/c/github/syntax-tree/unist-util-find-before.svg

[coverage]: https://codecov.io/github/syntax-tree/unist-util-find-before

[downloads-badge]: https://img.shields.io/npm/dm/unist-util-find-before.svg

[downloads]: https://www.npmjs.com/package/unist-util-find-before

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

[size]: https://bundlejs.com/?q=unist-util-find-before

[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://wooorm.com

[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

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

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

[test]: https://github.com/syntax-tree/unist-util-is#test

[api-findbefore]: #findbeforeparent-nodeindex-test