markdown-it/support/api_header.md

# markdown-it

## Install

**node.js**:

```bash
npm install markdown-it
```

**browser (CDN):**

- [jsDeliver CDN](http://www.jsdelivr.com/#!markdown-it "jsDelivr CDN")
- [cdnjs.com CDN](https://cdnjs.com/libraries/markdown-it "cdnjs.com")


## Usage examples

See also:

- [Development info](https://github.com/markdown-it/markdown-it/tree/master/docs) -
  for plugins writers.


### Simple

```js
// node.js
// can use `require('markdown-it')` for CJS
import markdownit from 'markdown-it'
const md = markdownit()
const result = md.render('# markdown-it rulezz!');

// browser with UMD build, added to "window" on script load
// Note, there is no dash in "markdownit".
const md = window.markdownit();
const result = md.render('# markdown-it rulezz!');
```

Single line rendering, without paragraph wrap:

```js
import markdownit from 'markdown-it'
const md = markdownit()
const result = md.renderInline('__markdown-it__ rulezz!');
```


### Init with presets and options

(*) presets define combinations of active rules and options. Can be
`"commonmark"`, `"zero"` or `"default"` (if skipped). See
[API docs](https://markdown-it.github.io/markdown-it/#MarkdownIt.new) for more details.

```js
import markdownit from 'markdown-it'

// commonmark mode
const md = markdownit('commonmark')

// default mode
const md = markdownit()

// enable everything
const md = markdownit({
  html: true,
  linkify: true,
  typographer: true
})

// full options list (defaults)
const md = markdownit({
  // Enable HTML tags in source
  html:         false,

  // Use '/' to close single tags (<br />).
  // This is only for full CommonMark compatibility.
  xhtmlOut:     false,

  // Convert '\n' in paragraphs into <br>
  breaks:       false,

  // CSS language prefix for fenced blocks. Can be
  // useful for external highlighters.
  langPrefix:   'language-',

  // Autoconvert URL-like text to links
  linkify:      false,

  // Enable some language-neutral replacement + quotes beautification
  // For the full list of replacements, see https://github.com/markdown-it/markdown-it/blob/master/lib/rules_core/replacements.mjs
  typographer:  false,

  // Double + single quotes replacement pairs, when typographer enabled,
  // and smartquotes on. Could be either a String or an Array.
  //
  // For example, you can use '«»„“' for Russian, '„“‚‘' for German,
  // and ['«\xA0', '\xA0»', '‹\xA0', '\xA0›'] for French (including nbsp).
  quotes: '“”‘’',

  // Highlighter function. Should return escaped HTML,
  // or '' if the source string is not changed and should be escaped externally.
  // If result starts with <pre... internal wrapper is skipped.
  highlight: function (/*str, lang*/) { return ''; }
});
```


### Plugins load

```js
import markdownit from 'markdown-it'

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


### Syntax highlighting

Apply syntax highlighting to fenced code blocks with the `highlight` option:

```js
import markdownit from 'markdown-it'
import hljs from 'highlight.js' // https://highlightjs.org

// Actual default values
const md = markdownit({
  highlight: function (str, lang) {
    if (lang && hljs.getLanguage(lang)) {
      try {
        return hljs.highlight(str, { language: lang }).value;
      } catch (__) {}
    }

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

Or with full wrapper override (if you need assign class to `<pre>` or `<code>`):

```js
import markdownit from 'markdown-it'
import hljs from 'highlight.js' // https://highlightjs.org

// Actual default values
const md = markdownit({
  highlight: function (str, lang) {
    if (lang && hljs.getLanguage(lang)) {
      try {
        return '<pre><code class="hljs">' +
               hljs.highlight(str, { language: lang, ignoreIllegals: true }).value +
               '</code></pre>';
      } catch (__) {}
    }

    return '<pre><code class="hljs">' + md.utils.escapeHtml(str) + '</code></pre>';
  }
});
```

### Linkify

`linkify: true` uses [linkify-it](https://github.com/markdown-it/linkify-it). To
configure linkify-it, access the linkify instance through `md.linkify`:

```js
md.linkify.set({ fuzzyEmail: false });  // disables converting email to link
```

## Syntax extensions

Embedded (enabled by default):

- [Tables](https://help.github.com/articles/organizing-information-with-tables/) (GFM)
- [Strikethrough](https://help.github.com/articles/basic-writing-and-formatting-syntax/#styling-text) (GFM)

Via plugins:

- [subscript](https://github.com/markdown-it/markdown-it-sub)
- [superscript](https://github.com/markdown-it/markdown-it-sup)
- [footnote](https://github.com/markdown-it/markdown-it-footnote)
- [definition list](https://github.com/markdown-it/markdown-it-deflist)
- [abbreviation](https://github.com/markdown-it/markdown-it-abbr)
- [emoji](https://github.com/markdown-it/markdown-it-emoji)
- [custom container](https://github.com/markdown-it/markdown-it-container)
- [insert](https://github.com/markdown-it/markdown-it-ins)
- [mark](https://github.com/markdown-it/markdown-it-mark)
- ... and [others](https://www.npmjs.org/browse/keyword/markdown-it-plugin)


### Manage rules

By default all rules are enabled, but can be restricted by options. On plugin
load all its rules are enabled automatically.

```js
import markdownit from 'markdown-it'

// Activate/deactivate rules, with currying
const md = markdownit()
  .disable(['link', 'image'])
  .enable(['link'])
  .enable('image');

// Enable everything
const md = markdownit({
  html: true,
  linkify: true,
  typographer: true,
});
```