unist-util-remove

unist utility to remove all nodes that pass a test from the tree.

Contents

• What is this?
• When should I use this?
• Install
• Use
• API
  • remove(tree[, options], test)
• Types
• Compatibility
• Related
• Contribute
• License

What is this?

This is a small utility that helps you clean a tree by removing some stuff.

When should I use this?

You can use this utility to remove things from a tree. This utility is very similar to unist-util-filter, which creates a new tree. Modifying a tree like this utility unist-util-remove does is much faster on larger documents though.

You can also walk the tree with unist-util-visit to remove nodes. To create trees, use unist-builder.

Install

This package is ESM only. In Node.js (version 12.20+, 14.14+, 16.0+, 18.0+), install with npm:

npm install unist-util-remove

In Deno with esm.sh:

import {remove} from "https://esm.sh/unist-util-remove@3"

In browsers with esm.sh:

<script type="module">
  import {remove} from "https://esm.sh/unist-util-remove@3?bundle"
</script>

Use

import {u} from 'unist-builder'
import {remove} from 'unist-util-remove'

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

// Remove all nodes of type `leaf`.
remove(tree, 'leaf')

console.dir(tree, {depth: null})

Yields:

{
  type: 'root',
  children: [
    {
      type: 'parent',
      children: [{type: 'parent', children: [{type: 'other', value: '4'}]}]
    }
  ]
}

👉 Note: the parent of leaf 5 is also removed, options.cascade can change that.

API

This package exports the identifier remove. There is no default export.

remove(tree[, options], test)

Mutate the given tree (Node) by removing all nodes that pass test (Test from unist-util-is). The tree is walked in preorder (NLR), visiting the node itself, then its head, etc.

options

Configuration (optional).

options.cascade

Whether to drop parent nodes if they had children, but all their children were filtered out (boolean, default: true).

Returns

The given tree without nodes that pass test (Node?). null is returned if tree itself didn’t pass the test or is cascaded away.

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 all maintained versions of Node.js. As of now, that is Node.js 12.20+, 14.14+, 16.0+, and 18.0+. Our projects sometimes work with older versions, but this is not guaranteed.

Related

• unist-util-filter — create a new tree with all nodes that pass the given function
• unist-util-flatmap — create a new tree by expanding a node into many
• unist-util-map — create a new tree by mapping nodes
• unist-util-select — select nodes with CSS-like selectors
• unist-util-visit — walk the tree
• unist-builder — create trees

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

License

MIT © Eugene Sharygin