remark - markdown processor powered by pluginsremark
Markdown processor powered by plugins
Core
remark is a markdown processor powered by plugins part of the unified collective. The project parses and compiles markdown, and lets programs process markdown without ever compiling to HTML (it can though). Powered by plugins to do all kinds of things: check markdown code style, add a table of contents, or compile to man pages.
View the project on GitHub or inspect the syntax tree on AST Explorer.
CLI
The Command Line Interface is powerful, it supports all settings the API provides and has built-in support for regenerating markdown files in a project according to a given style-guide, and emits warnings triggered by plugins in a beautiful fashion.
Say example.md
looks as follows:example.md* Hello
[World][]
Now, by running remark in a terminal we’ll see the following:shremark example.md --use remark-preset-lint-recommended
example.md
1:3 warning Incorrect list-item indent: add 2 spaces list-item-indent
3:1-3:10 warning Found reference to undefined definition no-undefined-references
⚠ 2 warnings
Read more about the CLI in its readme
.
API
The Application Programming Interface is the gist of remark and the CLI. It’s provided by unified
so head to its API documentation for more info.
Say we have the following index.js
file using remark, remark-preset-lint-markdown-style-guide
, remark-html
, and vfile-reporter
:index.jsimport {reporter} from 'vfile-reporter'
import {remark} from 'remark'
import remarkPresetLintMarkdownStyleGuide from 'remark-preset-lint-markdown-style-guide'
import remarkHtml from 'remark-html'
remark()
.use(remarkPresetLintMarkdownStyleGuide)
.use(remarkHtml)
.process('*emphasis* and _importance_')
.then((file) => {
console.log(String(file))
console.error(reporter(file))
})
Now, after installing dependencies and running index.js
with Node, you’ll see the following:shnpm install remark vfile-reporter remark-html remark-preset-lint-markdown-style-guide
/Users/tilde/example
├── remark@14.0.1
├── remark-html@14.0.0
├── remark-preset-lint-markdown-style-guide@5.0.0
└── vfile-reporter@7.0.1
node index.js
<p><em>emphasis</em> and <em>importance</em></p>
example.md
1:16-1:28 warning Emphasis should use `*` as a marker emphasis-marker
⚠ 1 warning
unified
unified is an interface for processing text with syntax trees and transforming between them. Three syntaxes are connected to unified, each coming with a syntax tree definition, and a parser and stringifier: mdast with remark for markdown, nlcst with retext for prose, and hast with rehype for HTML.
unified also bridges between syntaxes, such as between markdown and HTML, as can be seen below:index.jsimport {unified} from 'unified'
import stream from 'unified-stream'
import remarkParse from 'remark-parse'
import remarkToc from 'remark-toc'
import remarkRehype from 'remark-rehype'
import rehypeDocument from 'rehype-document'
import rehypeFormat from 'rehype-format'
import rehypeStringify from 'rehype-stringify'
const input = '## Markdown'
unified()
.use(remarkParse)
.use(remarkToc)
.use(remarkRehype)
.use(rehypeDocument, {title: 'Contents'})
.use(rehypeFormat)
.use(rehypeStringify)
.process(input)
.then((file) => {
console.log(file)
})
View the unified project on GitHub or peruse the website.