to-textile

An HTML to Textile converter written in JavaScript. This code is based on the original markdown converter by dom christie.

The API is as follows:

toTextile(stringOfHTML, options);

Installation

Browser

Download the compiled script located at dist/to-textile.min.js,

<script src="PATH/TO/to-textile.min.js"></script>
<script>toTextile('<h1>Hello world!</h1>')</script>

Node.js

Install the to-textile module:

$ npm install to-textile

Then you can use it like below:

var toTextile = require('to-textile');
toTextile('<h1>Hello world!</h1>');

Options

converters (array)

to-textile can be extended by passing in an array of converters to the options object:

toTextile(stringOfHTML, { converters: [converter1, converter2, …] });

A converter object consists of a filter, and a replacement. This example from the source replaces code elements:

{
  filter: 'code',
  replacement: function(content) {
    return '`' + content + '`';
  }
}

filter (string|array|function)

The filter property determines whether or not an element should be replaced. DOM nodes can be selected simply by filtering by tag name, with strings or with arrays of strings:

• filter: 'p' will select p elements
• filter: ['em', 'i'] will select em or i elements

Alternatively, the filter can be a function that returns a boolean depending on whether a given node should be replaced. The function is passed a DOM node as its only argument. For example, the following will match any span element with an italic font style:

filter: function (node) {
  return node.nodeName === 'SPAN' && /italic/i.test(node.style.fontStyle);
}

replacement (function)

The replacement function determines how an element should be converted. It should return the textile string for a given node. The function is passed the node’s content, as well as the node itself (used in more complex conversions). It is called in the context of toTextile, and therefore has access to the methods detailed below.

The following converter replaces heading elements (h1-h6):

{
  filter: ['h1', 'h2', 'h3', 'h4', 'h5', 'h6'],

  replacement: function(innerHTML, node) {
    var hLevel = node.tagName.charAt(1);
    var hPrefix = '';
    for(var i = 0; i < hLevel; i++) {
      hPrefix += '#';
    }
    return '\n' + hPrefix + ' ' + innerHTML + '\n\n';
  }
}

gfm (boolean)

to-textile has beta support for GitHub flavored textile (GFM). Set the gfm option to true:

toTextile('<del>Hello world!</del>', { gfm: true });

attributeBlocks (boolean) Default: true

Set attributeBlocks to false to disable textile attribute blocks.

ignorePotentialOlTriggers (boolean) Default: false

By default, to-textile adds an escape character (\) to numbers at the beginning of new lines. Set ignorePotentialOlTriggers to avoid this behavior.

Methods

The following methods can be called on the toTextile object.

isBlock(node)

Returns true/false depending on whether the element is block level.

isVoid(node)

Returns true/false depending on whether the element is void.

outer(node)

Returns the content of the node along with the element itself.

Development

First make sure you have node.js/npm installed, then:

$ npm install --dev

Automatically browserify the module when source files change by running:

$ npm start

Tests

To run the tests in the browser, open test/index.html.

To run in node.js:

$ npm test

Credits

Thanks to Dom Christie for the original markdown implementation.

Licence

to-textile is copyright © 2017+ cmroanirgo and released under the MIT license.