unist-util-find-after

What is unist-util-find-after?

The `unist-util-find-after` package is a utility for working with unist syntax trees. It allows you to find a node in a tree that comes after a given node, optionally matching a test function or type.

What are unist-util-find-after's main functionalities?

Find a node after a given node

This feature allows you to find the first node that comes after a given node in the tree. In this example, it finds the node that comes after the first paragraph.

const findAfter = require('unist-util-find-after');
const tree = { type: 'root', children: [
  { type: 'paragraph', children: [{ type: 'text', value: 'Hello' }] },
  { type: 'paragraph', children: [{ type: 'text', value: 'World' }] }
]};
const node = findAfter(tree, tree.children[0]);
console.log(node); // { type: 'paragraph', children: [{ type: 'text', value: 'World' }] }

Find a node after a given node matching a type

This feature allows you to find the first node of a specific type that comes after a given node. In this example, it finds the first heading node that comes after the first paragraph.

const findAfter = require('unist-util-find-after');
const tree = { type: 'root', children: [
  { type: 'paragraph', children: [{ type: 'text', value: 'Hello' }] },
  { type: 'heading', children: [{ type: 'text', value: 'Title' }] },
  { type: 'paragraph', children: [{ type: 'text', value: 'World' }] }
]};
const node = findAfter(tree, tree.children[0], 'heading');
console.log(node); // { type: 'heading', children: [{ type: 'text', value: 'Title' }] }

Find a node after a given node matching a test function

This feature allows you to find the first node that matches a test function and comes after a given node. In this example, it finds the paragraph node that contains the text 'World' after the first paragraph.

const findAfter = require('unist-util-find-after');
const tree = { type: 'root', children: [
  { type: 'paragraph', children: [{ type: 'text', value: 'Hello' }] },
  { type: 'heading', children: [{ type: 'text', value: 'Title' }] },
  { type: 'paragraph', children: [{ type: 'text', value: 'World' }] }
]};
const test = node => node.type === 'paragraph' && node.children[0].value === 'World';
const node = findAfter(tree, tree.children[0], test);
console.log(node); // { type: 'paragraph', children: [{ type: 'text', value: 'World' }] }

Other packages similar to unist-util-find-after

unist-util-visit

The `unist-util-visit` package is used to recursively walk through unist syntax trees. It allows you to visit nodes of a specific type or matching a test function. Unlike `unist-util-find-after`, it is more focused on traversal and visiting nodes rather than finding a specific node after another.

unist-util-select

The `unist-util-select` package provides a CSS-like selector API for unist syntax trees. It allows you to select nodes based on complex queries. While `unist-util-find-after` is focused on finding nodes after a given node, `unist-util-select` offers more powerful and flexible querying capabilities.

unist-util-filter

The `unist-util-filter` package is used to create a new tree with only the nodes that pass a test function. It is useful for filtering out unwanted nodes. In contrast, `unist-util-find-after` is specifically designed to find a single node that comes after another node.

README

unist-util-find-after

unist utility to find a node after another node.

Contents

• What is this?
• When should I use this?
• Install
• Use
• API
  • findAfter(parent, node|index[, test])
• Types
• Compatibility
• Related
• Contribute
• License

What is this?

This is a tiny utility that you can use to find a node after another node or after 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. In Node.js (version 16+), install with npm:

npm install unist-util-find-after

In Deno with esm.sh:

import {findAfter} from 'https://esm.sh/unist-util-find-after@5'

In browsers with esm.sh:

<script type="module">
  import {findAfter} from 'https://esm.sh/unist-util-find-after@5?bundle'
</script>

Use

import {u} from 'unist-builder'
import {findAfter} from 'unist-util-find-after'

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')
])

console.log(findAfter(tree, 1, 'parent'))

Yields:

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

API

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

findAfter(parent, node|index[, test])

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

Parameters

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

Returns

Child of parent (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-after@^5, compatible with Node.js 16.

Related

• 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) with the provided function and then flattening
• unist-util-find-before — find a node before 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-remove — remove nodes from a tree that pass a test
• unist-util-select — select nodes with CSS-like selectors

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 © Titus Wormer