lib/coderay.rb
# encoding: utf-8
# Encoding.default_internal = 'UTF-8'
# = 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:
#
# http://cycnus.de/raindark/coderay/scheme.png
#
# == 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">"Hello, world!"</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 <tt>:python</tt> or <tt>:html</tt>.
# * 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.
#
# CodeRay.scan:: Scan a string in a given language into Tokens.
# This is the most common method to use.
# CodeRay.scan_file:: Scan a file and guess the language using FileType.
#
# 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 <tt>:html</tt> or <tt>:statistic</tt>.
#
# CodeRay.encode:: Scan and encode a string in a given language.
# CodeRay.encode_tokens:: Encode the given tokens.
# CodeRay.encode_file:: Scan a file, guess the language using FileType and encode it.
#
# == All-in-One Encoding
#
# CodeRay.encode:: Highlight a string with a given input and output format.
#
# == Instanciating
#
# You can use an Encoder instance to highlight multiple inputs. This way, the setup
# for this Encoder must only be done once.
#
# CodeRay.encoder:: Create an Encoder instance with format and options.
# CodeRay.scanner:: Create an Scanner instance for lang, with '' as default code.
#
# 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.
module CodeRay
$CODERAY_DEBUG ||= false
CODERAY_PATH = File.expand_path('../coderay', __FILE__)
# Assuming the path is a subpath of lib/coderay/
def self.coderay_path *path
File.join CODERAY_PATH, *path
end
autoload :VERSION, 'coderay/version'
# helpers
autoload :FileType, coderay_path('helpers', 'file_type')
# Tokens
autoload :Tokens, coderay_path('tokens')
autoload :TokensProxy, coderay_path('tokens_proxy')
autoload :TokenKinds, coderay_path('token_kinds')
# Plugin system
autoload :PluginHost, coderay_path('helpers', 'plugin_host')
autoload :Plugin, coderay_path('helpers', 'plugin')
# Plugins
autoload :Scanners, coderay_path('scanners')
autoload :Encoders, coderay_path('encoders')
autoload :Styles, coderay_path('styles')
# convenience access and reusable Encoder/Scanner pair
autoload :Duo, coderay_path('duo')
class << self
# Scans the given +code+ (a String) with the Scanner for +lang+.
#
# This is a simple way to use CodeRay. Example:
# require 'coderay'
# page = CodeRay.scan("puts 'Hello, world!'", :ruby).html
#
# See also demo/demo_simple.
def scan code, lang, options = {}, &block
CodeRay::TokensProxy.new code, lang, options, block
end
# Scans +filename+ (a path to a code file) with the Scanner for +lang+.
#
# If +lang+ is :auto or omitted, the CodeRay::FileType module is used to
# determine it. If it cannot find out what type it is, it uses
# CodeRay::Scanners::Text.
#
# Calls CodeRay.scan.
#
# Example:
# require 'coderay'
# page = CodeRay.scan_file('some_c_code.c').html
def scan_file filename, lang = :auto, options = {}, &block
lang = CodeRay::FileType.fetch filename, :text, true if lang == :auto
code = File.read filename
scan code, lang, options, &block
end
# Encode a string.
#
# This scans +code+ with the the Scanner for +lang+ and then
# encodes it with the Encoder for +format+.
# +options+ will be passed to the Encoder.
#
# See CodeRay::Encoder.encode.
def encode code, lang, format, options = {}
encoder(format, options).encode code, lang, options
end
# Encode pre-scanned Tokens.
# Use this together with CodeRay.scan:
#
# require 'coderay'
#
# # Highlight a short Ruby code example in a HTML span
# tokens = CodeRay.scan '1 + 2', :ruby
# puts CodeRay.encode_tokens(tokens, :span)
#
def encode_tokens tokens, format, options = {}
encoder(format, options).encode_tokens tokens, options
end
# Encodes +filename+ (a path to a code file) with the Scanner for +lang+.
#
# See CodeRay.scan_file.
# Notice that the second argument is the output +format+, not the input language.
#
# Example:
# require 'coderay'
# page = CodeRay.encode_file 'some_c_code.c', :html
def encode_file filename, format, options = {}
tokens = scan_file filename, :auto, get_scanner_options(options)
encode_tokens tokens, format, options
end
# Highlight a string into a HTML <div>.
#
# CSS styles use classes, so you have to include a stylesheet
# in your output.
#
# See encode.
def highlight code, lang, options = { :css => :class }, format = :div
encode code, lang, format, options
end
# Highlight a file into a HTML <div>.
#
# CSS styles use classes, so you have to include a stylesheet
# in your output.
#
# See encode.
def highlight_file filename, options = { :css => :class }, format = :div
encode_file filename, format, options
end
# Finds the Encoder class for +format+ and creates an instance, passing
# +options+ to it.
#
# Example:
# require 'coderay'
#
# stats = CodeRay.encoder(:statistic)
# stats.encode("puts 17 + 4\n", :ruby)
#
# puts '%d out of %d tokens have the kind :integer.' % [
# stats.type_stats[:integer].count,
# stats.real_token_count
# ]
# #-> 2 out of 4 tokens have the kind :integer.
def encoder format, options = {}
CodeRay::Encoders[format].new options
end
# Finds the Scanner class for +lang+ and creates an instance, passing
# +options+ to it.
#
# See Scanner.new.
def scanner lang, options = {}, &block
CodeRay::Scanners[lang].new '', options, &block
end
# Extract the options for the scanner from the +options+ hash.
#
# Returns an empty Hash if <tt>:scanner_options</tt> is not set.
#
# This is used if a method like CodeRay.encode has to provide options
# for Encoder _and_ scanner.
def get_scanner_options options
options.fetch :scanner_options, {}
end
end
end