mdast-util-gfm

What is mdast-util-gfm?

The `mdast-util-gfm` package is a utility for working with GitHub Flavored Markdown (GFM) in the MDAST (Markdown Abstract Syntax Tree) format. It provides functions to parse and transform GFM-specific syntax such as tables, strikethroughs, task lists, and autolinks.

What are mdast-util-gfm's main functionalities?

Tables

This feature allows you to parse and transform GitHub Flavored Markdown tables into an MDAST tree structure.

const { fromMarkdown, toMarkdown } = require('mdast-util-gfm');
const markdown = '| Header1 | Header2 |
| ------- | ------- |
| Cell1   | Cell2   |';
const tree = fromMarkdown(markdown);
console.log(tree);

Strikethrough

This feature allows you to parse and transform strikethrough text in GitHub Flavored Markdown into an MDAST tree structure.

const { fromMarkdown, toMarkdown } = require('mdast-util-gfm');
const markdown = 'This is ~~strikethrough~~ text.';
const tree = fromMarkdown(markdown);
console.log(tree);

Task Lists

This feature allows you to parse and transform task lists in GitHub Flavored Markdown into an MDAST tree structure.

const { fromMarkdown, toMarkdown } = require('mdast-util-gfm');
const markdown = '- [x] Task 1
- [ ] Task 2';
const tree = fromMarkdown(markdown);
console.log(tree);

Autolinks

This feature allows you to parse and transform autolinks in GitHub Flavored Markdown into an MDAST tree structure.

const { fromMarkdown, toMarkdown } = require('mdast-util-gfm');
const markdown = 'Visit https://example.com for more info.';
const tree = fromMarkdown(markdown);
console.log(tree);

Other packages similar to mdast-util-gfm

remark-gfm

The `remark-gfm` package is a plugin for the `remark` ecosystem that adds support for GitHub Flavored Markdown. It provides similar functionality to `mdast-util-gfm` but is designed to be used within the `remark` processor.

markdown-it

The `markdown-it` package is a Markdown parser that supports GitHub Flavored Markdown out of the box. It is a more general-purpose parser compared to `mdast-util-gfm`, which is specifically designed for working with MDAST.

marked

The `marked` package is a fast Markdown parser and compiler that supports GitHub Flavored Markdown. It is similar to `markdown-it` in that it is a general-purpose parser, but it is known for its speed and performance.

README

mdast-util-gfm

Extension for mdast-util-from-markdown and/or mdast-util-to-markdown to support GitHub flavored markdown in mdast. When parsing (from-markdown), must be combined with micromark-extension-gfm.

You probably shouldn’t use this package directly, but instead use remark-gfm with remark.

Alternatively, the extensions can be used separately:

• syntax-tree/mdast-util-gfm-autolink-literal — support GFM autolink literals
• syntax-tree/mdast-util-gfm-strikethrough — support GFM strikethrough
• syntax-tree/mdast-util-gfm-table — support GFM tables
• syntax-tree/mdast-util-gfm-task-list-item — support GFM tasklists

Install

npm:

npm install mdast-util-gfm

Use

Say we have the following file, example.md:

# GFM

## Autolink literals

www.example.com, https://example.com, and [e-mail].

## Strikethrough

~one~ or ~~two~~ tildes.

## Table

| a | b  |  c |  d  |
| - | :- | -: | :-: |

## Tasklist

* [ ] to do
* [x] done

And our script, example.js, looks as follows:

var fs = require('fs')
var fromMarkdown = require('mdast-util-from-markdown')
var toMarkdown = require('mdast-util-to-markdown')
var syntax = require('micromark-extension-gfm')
var gfm = require('mdast-util-gfm')

var doc = fs.readFileSync('example.md')

var tree = fromMarkdown(doc, {
  extensions: [syntax()],
  mdastExtensions: [gfm.fromMarkdown]
})

console.log(tree)

var out = toMarkdown(tree, {extensions: [gfm.toMarkdown()]})

console.log(out)

Now, running node example yields:

{
  type: 'root',
  children: [
    {type: 'heading', depth: 1, children: [{type: 'text', value: 'GFM'}]},
    {
      type: 'heading',
      depth: 2,
      children: [{type: 'text', value: 'Autolink literals'}]
    },
    {
      type: 'paragraph',
      children: [
        {
          type: 'link',
          title: null,
          url: 'http://www.example.com',
          children: [{type: 'text', value: 'www.example.com'}]
        },
        {type: 'text', value: ', '},
        {
          type: 'link',
          title: null,
          url: 'https://example.com',
          children: [{type: 'text', value: 'https://example.com'}]
        },
        {type: 'text', value: ', and '},
        {
          type: 'link',
          title: null,
          url: 'mailto:[e-mail]',
          children: [{type: 'text', value: '[e-mail]'}]
        },
        {type: 'text', value: '.'}
      ]
    },
    {
      type: 'heading',
      depth: 2,
      children: [{type: 'text', value: 'Strikethrough'}]
    },
    {
      type: 'paragraph',
      children: [
        {
          type: 'delete',
          children: [{type: 'text', value: 'one'}]
        },
        {type: 'text', value: ' or '},
        {
          type: 'delete',
          children: [{type: 'text', value: 'two'}]
        },
        {type: 'text', value: ' tildes.'}
      ]
    },
    {type: 'heading', depth: 2, children: [{type: 'text', value: 'Table'}]},
    {
      type: 'table',
      align: [null, 'left', 'right', 'center'],
      children: [
        {
          type: 'tableRow',
          children: [
            {type: 'tableCell', children: [{type: 'text', value: 'a'}]},
            {type: 'tableCell', children: [{type: 'text', value: 'b'}]},
            {type: 'tableCell', children: [{type: 'text', value: 'c'}]},
            {type: 'tableCell', children: [{type: 'text', value: 'd'}]}
          ]
        }
      ]
    },
    {type: 'heading', depth: 2, children: [{type: 'text', value: 'Tasklist'}]},
    {
      type: 'list',
      ordered: false,
      start: null,
      spread: false,
      children: [
        {
          type: 'listItem',
          spread: false,
          checked: false,
          children: [
            {type: 'paragraph', children: [{type: 'text', value: 'to do'}]}
          ]
        },
        {
          type: 'listItem',
          spread: false,
          checked: true,
          children: [
            {type: 'paragraph', children: [{type: 'text', value: 'done'}]}
          ]
        }
      ]
    }
  ]
}

# GFM

## Autolink literals

[www.example.com](http://www.example.com), <https://example.com>, and <[e-mail]>.

## Strikethrough

~~one~~ or ~~two~~ tildes.

## Table

| a | b  |  c |  d  |
| - | :- | -: | :-: |

## Tasklist

*   [ ] to do
*   [x] done

API

gfm.fromMarkdown

gfm.toMarkdown(options?)

Note: the separate extensions are also available at mdast-util-gfm/from-markdown and mdast-util-gfm/to-markdown.

Support GFM. The exports of fromMarkdown is an extension for mdast-util-from-markdown. The export of toMarkdown is a function that can be called with options and returns an extension for mdast-util-to-markdown.

options

Passed as options to mdast-util-gfm-table.

The exports are extensions, respectively for mdast-util-from-markdown and mdast-util-to-markdown.

Related

• remarkjs/remark — markdown processor powered by plugins
• remarkjs/remark-gfm — remark plugin to support GFM
• micromark/micromark — the smallest commonmark-compliant markdown parser that exists
• micromark/micromark-extension-gfm — micromark extension to parse GFM
• syntax-tree/mdast-util-from-markdown — mdast parser using micromark to create mdast from markdown
• syntax-tree/mdast-util-to-markdown — mdast serializer to create markdown from mdast

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