Ruby/RubyMotion version of Markdown-it (CommonMark compliant and extendable)
This gem is a port of the markdown-it Javascript package by Vitaly Puzrin and Alex Kocharin.
Currently synced with markdown-it 13.0.1
Follows the CommonMark spec + adds syntax extensions & sugar (URL autolinking, typographer).
- Configurable syntax. You can add new rules and even replace existing ones.
- Safe by default.
- Community-written plugins
- Ruby/RubyMotion
- original javascript plugins and other packages on npm.
 
The benefit of this project, for me at least, is to have a standardized CommonMark compliant, fast, and extendable, Markdown parser which can be used from Javascript, Ruby, and/or RubyMotion, as the development situation warrants.
Performance is slower than, say, kramdown, but for most uses, is pretty fast.  Here are some non-scientific benchmarks.  Note that kramdown and redcarpet are not CommonMark compliant.
Running tests on 2018-04-04 under ruby 2.3.1p112 (2016-04-26 revision 54768) [x86_64-darwin16]
==> Test using file mdsyntax.text and 500 runs
Rehearsal -------------------------------------------------------------
motion-markdown-it 8.4.1   17.940000   0.710000  18.650000 ( 18.721629)
kramdown 1.16.2            14.720000   0.180000  14.900000 ( 15.015840)
commonmarker 0.17.9         0.220000   0.000000   0.220000 (  0.222098)
redcarpet 3.4.0             0.140000   0.010000   0.150000 (  0.145821)
--------------------------------------------------- total: 33.920000sec
                                user     system      total        real
motion-markdown-it 8.4.1   18.290000   0.720000  19.010000 ( 19.113943)
kramdown 1.16.2            13.320000   0.110000  13.430000 ( 13.459096)
commonmarker 0.17.9         0.190000   0.000000   0.190000 (  0.187104)
redcarpet 3.4.0             0.120000   0.000000   0.120000 (  0.123931)
Real time as a factor of motion-markdown-it
motion-markdown-it 8.4.1    1.0
kramdown 1.16.2             0.7042
commonmarker 0.17.9         0.0098
redcarpet 3.4.0             0.0065
Add it to your project's Gemfile
gem 'motion-markdown-it'
and run bundle install
Add it to your project's Gemfile
gem 'motion-markdown-it'
Edit your Rakefile and add
require 'motion-markdown-it'
and run bundle install
parser = MarkdownIt::Parser.new(:commonmark, { html: false })
parser.render('# markdown-it in **Ruby**')Single line rendering, without paragraph wrap:
result = MarkdownIt::Parser.new.renderInline('__markdown-it__ in Ruby')(*) presets define combinations of active rules and options. Can be
:commonmark, :zero or :default (if skipped).
#--- commonmark mode
parser = MarkdownIt::Parser.new(:commonmark)
#--- default mode
parser = MarkdownIt::Parser.new
#--- enable everything
parser = MarkdownIt::Parser.new({ html: true, linkify: true, typographer: true })
#--- full options list (defaults)
parser = MarkdownIt::Parser.new({
  html:         false,        # Enable HTML tags in source
  xhtmlOut:     false,        # Use '/' to close single tags (<br />).
                              # This is only for full CommonMark compatibility.
  breaks:       false,        # Convert '\n' in paragraphs into <br>
  langPrefix:   'language-',  # CSS language prefix for fenced blocks. Can be
                              # useful for external highlighters.
  linkify:      false,        # Autoconvert URL-like text to links
  # 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.js
  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 nil if the source string is not changed and should be escaped externally.
  highlight: lambda {|str, lang| return nil}
})Plugins can be used to extend the syntax and functionality. A sample set of plugins has been created based on those already created for the javascript version. Included are:
Upgrading to 8.4.1.2 could cause some small breakage if you are using any custom plugins.  The motion-markdown-it-plugins plugins have already been upgraded.
Make sure you have
include MarkdownIt::Common::Utilsat the top of your plugin file.  Then change any references to charCodeAt.  For example,
state.src.charCodeAt(pos)would become
charCodeAt(state.src, pos)slice_to_end has been removed.  Change references like this
state.src.slice_to_end(pos)to
state.src[pos..-1]Thanks to the authors of the original implementation in Javascript, markdown-it:
- Alex Kocharin github/rlidwka
- Vitaly Puzrin github/puzrin
and to John MacFarlane for his work on the CommonMark spec and reference implementations.
Related Links:
- https://github.com/jgm/CommonMark - reference CommonMark implementations in C & JS, also contains latest spec & online demo.
- http://talk.commonmark.org - CommonMark forum, good place to collaborate developers' efforts.