hast-util-is-element

What is hast-util-is-element?

The hast-util-is-element package is a utility for working with HAST (Hypertext Abstract Syntax Tree) nodes. It provides functions to check if a node is an element and optionally matches a given tag name. This is particularly useful when manipulating or inspecting HTML represented within JavaScript.

What are hast-util-is-element's main functionalities?

Check if a node is an element

This feature allows you to verify if a given node is an element node within a HAST structure. It's useful for filtering or processing nodes in a tree.

const isElement = require('hast-util-is-element');

const node = {type: 'element', tagName: 'div'};
console.log(isElement(node)); // Outputs: true

Check if a node is a specific element

This feature extends the basic check to allow for specification of the tag name. It's useful for finding or working with specific types of elements in a document.

const isElement = require('hast-util-is-element');

const node = {type: 'element', tagName: 'span'};
console.log(isElement(node, 'span')); // Outputs: true

Other packages similar to hast-util-is-element

unist-util-is

This package offers a more generalized approach for checking node types in unist trees, which is a part of the broader unified ecosystem. Unlike hast-util-is-element, unist-util-is can be used with different syntax trees beyond HTML, offering greater flexibility.

hast-util-has-property

Similar in utility scope within the HAST ecosystem, this package checks for the presence of properties in elements. While hast-util-is-element focuses on the type and tag name of nodes, hast-util-has-property deals with the properties of those nodes, providing a complementary functionality.

README

hast-util-is-element

Check if a node is a (certain) HAST element.

Installation

npm:

npm install hast-util-is-element

Usage

var is = require('hast-util-is-element')

is({type: 'text', value: 'foo'}) // => false

is({type: 'element', tagName: 'a'}, 'a') // => true

is({type: 'element', tagName: 'a'}, ['a', 'area']) // => true

API

isElement(node[, tagName|tagNames])

Check if a node is a (certain) HAST element.

When not given a second parameter, asserts if node is an element, otherwise asserts node is an element whose tagName matches / is included in the second parameter.

Parameters

• node (*) — Value to check;
• tagName (string, optional) — Value nodes tagName must match;
• tagNames (Array.<string>, optional) — Value including nodes tagName.

Returns

boolean — whether node passes the test.

Throws

Error — When the second parameter is given but invalid.

Contribute

See contributing.md in syntax-tree/hast for ways to get started.

This organisation has a Code of Conduct. By interacting with this repository, organisation, or community you agree to abide by its terms.

License

MIT © Titus Wormer