syntax-tree/unist-util-position

utility to get the position of a node

unist-util-position

unist utility to get positional info of nodes.

Contents

• What is this?
• When should I use this?
• Install
• Use
• API
  • position(node)
  • pointEnd(node)
  • pointStart(node)
• Types
• Compatibility
• Related
• Contribute
• 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 you’re 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 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 when you want to display positional info to users.

Install

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

npm install unist-util-position

In Deno with esm.sh:

import {pointEnd, pointStart, position} from 'https://esm.sh/unist-util-position@5'

In browsers with esm.sh:

<script type="module">
  import {pointEnd, pointStart, position} from 'https://esm.sh/unist-util-position@5?bundle'
</script>

Use

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:

{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, pointStart, and position. There is no default export.

position(node)

Get the positional info of node.

Parameters

• node (Node) — node

Returns

Position, if valid (Position or undefined).

pointEnd(node)

Get the ending point of node.

Parameters

• node (Node) — node

Returns

Point, if valid (Point or undefined).

pointStart(node)

Get the starting point of node.

Parameters

• node (Node) — node

Returns

Point, if valid (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 — serialize a node, position, or point as a human readable location
• unist-util-position-from-estree — get a position from an estree node
• unist-util-remove-position — remove positions from tree
• unist-util-generated — check if a node is generated
• unist-util-source — get the source of a node

Contribute

See contributing.md in syntax-tree/.github for ways to get started. See support.md for ways to get help.

This project has a code of conduct. By interacting with this repository, organization, or community you agree to abide by its terms.

License

MIT © Titus Wormer