site/node_modules/unist-util-position/readme.md

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# unist-util-position
[![Build][build-badge]][build]
[![Coverage][coverage-badge]][coverage]
[![Downloads][downloads-badge]][downloads]
[![Size][size-badge]][size]
[![Sponsors][sponsors-badge]][collective]
[![Backers][backers-badge]][collective]
[![Chat][chat-badge]][chat]
[unist][] utility to get positional info of nodes.
## Contents
* [What is this?](#what-is-this)
* [When should I use this?](#when-should-i-use-this)
* [Install](#install)
* [Use](#use)
* [API](#api)
* [`position(node)`](#positionnode)
* [`pointEnd(node)`](#pointendnode)
* [`pointStart(node)`](#pointstartnode)
* [Types](#types)
* [Compatibility](#compatibility)
* [Related](#related)
* [Contribute](#contribute)
* [License](#license)
## What is this?
This utility helps with accessing positional info on a potentially dirty tree.
## When should I use this?
The positional info is typically consistent and proper in unist trees generated
by our ecosystem, but, user plugins could mess that up.
If youre making a reusable plugin, and accessing the positional info often, you
might want to guard against that by using this utility.
You might also find the utility [`unist-util-generated`][unist-util-generated]
useful to check whether a node is considered to be generated (not in the
original input file).
You might also enjoy
[`unist-util-stringify-position`][unist-util-stringify-position] when you want
to display positional info to users.
## Install
This package is [ESM only][esm].
In Node.js (version 16+), install with [npm][]:
```sh
npm install unist-util-position
```
In Deno with [`esm.sh`][esmsh]:
```js
import {pointEnd, pointStart, position} from 'https://esm.sh/unist-util-position@5'
```
In browsers with [`esm.sh`][esmsh]:
```html
<script type="module">
import {pointEnd, pointStart, position} from 'https://esm.sh/unist-util-position@5?bundle'
</script>
```
## Use
```js
import {fromMarkdown} from 'mdast-util-from-markdown'
import {pointEnd, pointStart, position} from 'unist-util-position'
const tree = fromMarkdown('# foo\n\n* bar\n')
console.log(position(tree))
console.log(pointStart(tree))
console.log(pointEnd(tree))
```
Yields:
```js
{start: {line: 1, column: 1, offset: 0}, end: {line: 4, column: 1, offset: 13}}
{line: 1, column: 1, offset: 0}
{line: 4, column: 1, offset: 13}
```
## API
This package exports the identifiers [`pointEnd`][pointend],
[`pointStart`][pointstart], and [`position`][position].
There is no default export.
### `position(node)`
Get the positional info of `node`.
###### Parameters
* `node` ([`Node`][node])
— node
###### Returns
Position, if valid ([`Position`][unist-position] or `undefined`).
### `pointEnd(node)`
Get the ending point of `node`.
###### Parameters
* `node` ([`Node`][node])
— node
###### Returns
Point, if valid ([`Point`][unist-point] or `undefined`).
### `pointStart(node)`
Get the starting point of `node`.
###### Parameters
* `node` ([`Node`][node])
— node
###### Returns
Point, if valid ([`Point`][unist-point] or `undefined`).
## Types
This package is fully typed with [TypeScript][].
It exports no additional types.
## 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-position@^5`,
compatible with Node.js 16.
## Related
* [`unist-util-stringify-position`](https://github.com/syntax-tree/unist-util-stringify-position)
— serialize a node, position, or point as a human readable location
* [`unist-util-position-from-estree`](https://github.com/syntax-tree/unist-util-position-from-estree)
— get a position from an estree node
* [`unist-util-remove-position`](https://github.com/syntax-tree/unist-util-remove-position)
— remove positions from tree
* [`unist-util-generated`](https://github.com/syntax-tree/unist-util-generated)
— check if a node is generated
* [`unist-util-source`](https://github.com/syntax-tree/unist-util-source)
— get the source of a node
## 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] © [Titus Wormer][author]
<!-- Definitions -->
[build-badge]: https://github.com/syntax-tree/unist-util-position/workflows/main/badge.svg
[build]: https://github.com/syntax-tree/unist-util-position/actions
[coverage-badge]: https://img.shields.io/codecov/c/github/syntax-tree/unist-util-position.svg
[coverage]: https://codecov.io/github/syntax-tree/unist-util-position
[downloads-badge]: https://img.shields.io/npm/dm/unist-util-position.svg
[downloads]: https://www.npmjs.com/package/unist-util-position
[size-badge]: https://img.shields.io/badge/dynamic/json?label=minzipped%20size&query=$.size.compressedSize&url=https://deno.bundlejs.com/?q=unist-util-position
[size]: https://bundlejs.com/?q=unist-util-position
[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
[unist-position]: https://github.com/syntax-tree/unist#position
[unist-point]: https://github.com/syntax-tree/unist#point
[unist-util-generated]: https://github.com/syntax-tree/unist-util-generated
[unist-util-stringify-position]: https://github.com/syntax-tree/unist-util-stringify-position
[position]: #positionnode
[pointend]: #pointendnode
[pointstart]: #pointstartnode