markdown-it/README.md

remarkable
==========

[![Build Status](https://travis-ci.org/jonschlinkert/remarkable.svg?branch=master)](https://travis-ci.org/jonschlinkert/remarkable)
[![NPM version](https://img.shields.io/npm/v/remarkable.svg)](https://www.npmjs.org/package/remarkable)

Markdown parser done right. Fast and easy to extend.

__[Live demo](https://jonschlinkert.github.io/remarkable/demo/)__

- Configurable syntax! You can add new rules and even replace existing ones.
- Implements [CommonMark](http://commonmark.org/) spec +
  [syntax extentions](#syntax-extentions) + sugar (URL autolinking, typographer).
- Very high speed.


## Install

node.js:

```bash
npm install remarkable --save
```

bower:

```bash
bower install remarkable --save
```

CDNs for browser: [jsDeliver](http://www.jsdelivr.com/#!remarkable "jsDelivr CDN")


## Usage

```js
var Remarkable = require('remarkable');

// This values are default
var md = new Remarkable(/* "default" */, {
  html:         false,        // Enable HTML tags in source
  xhtmlOut:     false,        // Use '/' to close single tags (<br />)
  breaks:       false,        // Convert '\n' in paragraphs into <br>
  langPrefix:   'language-',  // CSS language prefix for fenced blocks
  linkify:      false,        // Autoconvert URL-like texts to links
  typographer:  false,        // Enable smartypants and other sweet transforms

  // Highlighter function. Should return escaped HTML,
  // or '' if input not changed
  highlight: function (/*str, , lang*/) { return ''; }
});

console.log(md.render('# Remarkable rulezz!'));
// => <h1>Remarkable rulezz!</h1>
```

You can define options via `set` method:

```js
var Remarkable = require('remarkable');
var md = new Remarkable('full');

md.set({
  html: true,
  breaks: true
});
```

__Note:__ To achieve best performance, don't modify the `Remarkable` instance on
the fly. If you need several configurations, create multiple instances and
initialise each appropriately.

Remarkable provides presets to quickly manage active syntax rules and options.
You can reset parser to strict [CommonMark](http://commonmark.org/) mode:

```js
var Remarkable = require('remarkable');
var md = new Remarkable('commonmark');
```

Or you can enable everything:

```js
var Remarkable = require('remarkable');
var md = new Remarkable('full');
```

By default remarkable is configured to be similar to GFM, but with disabled HTML.


### Highlight fenced blocks

To highlight content of fenced block, assign function to `highlight` option:

```js
var Remarkable = require('remarkable');
var hljs       = require('highlight.js') // https://highlightjs.org/

// These values are default
var md = new Remarkable({
  highlight: function (str, lang) {
    if (lang && hljs.getLanguage(lang)) {
      try {
        return hljs.highlight(lang, str).value;
      } catch (__) {}
    }

    try {
      return hljs.highlightAuto(str).value;
    } catch (__) {}

    return ''; // use external default escaping
  }
});
```


### Syntax extentions

Enabled by default:

- [Tables](https://help.github.com/articles/github-flavored-markdown/#tables) (GFM)
- [\<del>](https://help.github.com/articles/github-flavored-markdown/#strikethrough) (GFM strikethrough) - `~~deleted text~~`

Disabled by default:

- __\<ins>__ - `++inserted text++` (experimental)
- __\<mark>__ - `==marked text==` (experimental)

__*__ Experimental extentions can be changed later for something like
[Critic Markup](http://criticmarkup.com/). Though, you will be able to use
old-style rules via external plugins, if you like those.

Manage rules:

```js
var md = new Remarkable();
md.inline.ruler.enable([ 'ins', 'mark' ]);
md.block.ruler.disable([ 'table' ]);

// Enable everything
md = new Remarkable('full', {
  html: true,
  linkify: true,
  typographer: true,
});
```

### Typographer

Though full-weight typographic replacements are language specific, `remarkable`
provides the most common and universal case coverage:

```js
var Remarkable = require('remarkable');
var md = new Remarkable({ typographer: true });

// These values are default
md.typographer.set({
  singleQuotes: '‘’', // set empty to disable
  doubleQuotes: '“”', // set '«»' for Russian, '„“' for German, empty to disable
  copyright:    true, // (c) (C) → ©
  trademark:    true, // (tm) (TM) → ™
  registered:   true, // (r) (R) → ®
  plusminus:    true, // +- → ±
  paragraph:    true, // (p) (P) -> §
  ellipsis:     true, // ... → … (also ?.... → ?.., !.... → !..)
  dupes:        true, // ???????? → ???, !!!!! → !!!, `,,` → `,`
  dashes:       true  // -- → &ndash;, --- → &mdash;
})
```

Of course, you can add your own rules or replace default ones with something
more advanced, specific for your language.


## References / Thanks

Big thanks to [John MacFarlane](https://github.com/jgm) for his work on the
CommonMark spec and reference implementations. His work saved us a lot of time
during this project's development.

Links:

1. https://github.com/jgm/CommonMark - reference CommonMark implementations in C & JS,
   also contains latest spec & online demo.
2. http://talk.commonmark.org - CommonMark forum, good place to collaborate
   developers' efforts.


## Development / Modification

Parser consists of several responsibilities chains, filled with rules. You can
reconfigure anyone as you wish. Render also can be modified and extended. See
source code to understand details. Pay attention to these properties:

```js
Remarkable.block
Remarkable.block.ruler
Remarkable.inline
Remarkable.inline.ruler
Remarkable.typographer
Remarkable.typographer.ruler
Remarkable.linkifier
Remarkable.linkifier.ruler
Remarkable.renderer
Remarkable.renderer.rules
```

To prettify plugins init, `Remarked` has `.use()` helper for curried calls:

```js
var md = new Remarkable();

md.use(plugin1)
  .use(plugin2, opts)
  .use(plugin3);
```

## Authors

- Jon Schlinkert [github/jonschlinkert](https://github.com/jonschlinkert)
- Alex Kocharin [github/rlidwka](https://github.com/rlidwka)
- Vitaly Puzrin [github/puzrin](https://github.com/puzrin)


## License

[MIT](https://github.com/jonschlinkert/remarkable/blob/master/LICENSE)