Unist-util-remove NPM

unist-util-remove

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

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 16+), install with npm:

npm install unist-util-remove

In Deno with esm.sh:

import {remove} from 'https://esm.sh/unist-util-remove@4'

In browsers with esm.sh:

<script type="module">
  import {remove} from 'https://esm.sh/unist-util-remove@4?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: undefined})

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)`

Change the given tree by removing all nodes that pass test.

tree itself is never tested. The tree is walked in preorder (NLR), visiting the node itself, then its head, etc.

Parameters

tree (Node) — tree to change
options (Options, optional) — configuration
test (Test, optional) — unist-util-is compatible test

Returns

Nothing (undefined).

`Options`

Configuration (TypeScript type).

Fields

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

Types

This package is fully typed with TypeScript. It exports the additional type 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, unist-util-remove@^4, compatible with Node.js 16.

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