CodeRay Library

CodeRay is a Ruby library for syntax highlighting.

I try to make CodeRay easy to use and intuitive, but at the same time fully featured, complete, fast and efficient.

See README.

It consists mainly of

• the main engine: CodeRay (Scanners::Scanner, Tokens, Encoders::Encoder)

• the plugin system: PluginHost, Plugin

• the scanners in CodeRay::Scanners

• the encoders in CodeRay::Encoders

• the styles in CodeRay::Styles

Here’s a fancy graphic to light up this gray docu:

Documentation

See CodeRay, Encoders, Scanners, Tokens.

Usage

Remember you need RubyGems to use CodeRay, unless you have it in your load path. Run Ruby with -rubygems option if required.

Highlight Ruby code in a string as html

  require 'coderay'
  print CodeRay.scan('puts "Hello, world!"', :ruby).html

  # prints something like this:
  puts <span class="s">&quot;Hello, world!&quot;</span>

Highlight C code from a file in a html div

  require 'coderay'
  print CodeRay.scan(File.read('ruby.h'), :c).div
  print CodeRay.scan_file('ruby.h').html.div

You can include this div in your page. The used CSS styles can be printed with

  % coderay_stylesheet

Highlight without typing too much

If you are one of the hasty (or lazy, or extremely curious) people, just run this file:

  % ruby -rubygems /path/to/coderay/coderay.rb > example.html

and look at the file it created in your browser.

CodeRay Module

The CodeRay module provides convenience methods for the engine.

• The lang and format arguments select Scanner and Encoder to use. These are simply lower-case symbols, like :python or :html.

• All methods take an optional hash as last parameter, options, that is send to the Encoder / Scanner.

• Input and language are always sorted in this order: code, lang. (This is in alphabetical order, if you need a mnemonic ;)

You should be able to highlight everything you want just using these methods; so there is no need to dive into CodeRay’s deep class hierarchy.

The examples in the demo directory demonstrate common cases using this interface.

Basic Access Ways

Read this to get a general view what CodeRay provides.

Scanning

 
 Scanning means analysing an input string, splitting it up into Tokens.
 Each Token knows about what type it is: string, comment, class name, etc.

 Each +lang+ (language) has its own Scanner; for example, <tt>:ruby</tt> code is
 handled by CodeRay::Scanners::Ruby.

The Tokens object you get from these methods can encode itself; see Tokens.

Encoding

Encoding means compiling Tokens into an output. This can be colored HTML or LaTeX, a textual statistic or just the number of non-whitespace tokens.

Each Encoder provides output in a specific format, so you select Encoders via formats like :html or :statistic.

All-in-One Encoding

Instanciating

You can use an Encoder instance to highlight multiple inputs. This way, the setup for this Encoder must only be done once.

To make use of CodeRay.scanner, use CodeRay::Scanner::code=.

The scanning methods provide more flexibility; we recommend to use these.

Reusing Scanners and Encoders

If you want to re-use scanners and encoders (because that is faster), see CodeRay::Duo for the most convenient (and recommended) interface.

encoding: utf-8

encoding: ASCII-8BIT

encoding: utf-8

encoding: utf-8