comparison vendor/plugins/coderay-0.9.2/lib/.svn/text-base/coderay.rb.svn-base @ 0:513646585e45

* Import Redmine trunk SVN rev 3859

+# = 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/TokenStream, Encoders::Encoder), PluginHost
+# * the scanners in CodeRay::Scanners
+# * the encoders in CodeRay::Encoders
+# 
+# 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">&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 <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.
+#
+# == Streaming
+#
+# Streaming saves RAM by running Scanner and Encoder in some sort of
+# pipe mode; see TokenStream.
+#
+# CodeRay.scan_stream:: Scan in stream mode.
+#
+# == 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
+  
+  # Version: Major.Minor.Teeny[.Revision]
+  # Major: 0 for pre-stable, 1 for stable
+  # Minor: feature milestone
+  # Teeny: development state, 0 for pre-release
+  # Revision: Subversion Revision number (generated on rake gem:make)
+  VERSION = '0.9.2'
+
+  require 'coderay/tokens'
+  require 'coderay/token_classes'
+  require 'coderay/scanner'
+  require 'coderay/encoder'
+  require 'coderay/duo'
+  require 'coderay/style'
+
+
+  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
+      scanner = Scanners[lang].new code, options, &block
+      scanner.tokenize
+    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::Plaintext.
+    #
+    # Calls CodeRay.scan.
+    #
+    # Example:
+    #  require 'coderay'
+    #  page = CodeRay.scan_file('some_c_code.c').html
+    def scan_file filename, lang = :auto, options = {}, &block
+      file = IO.read filename
+      if lang == :auto
+        require 'coderay/helpers/file_type'
+        lang = FileType.fetch filename, :plaintext, true
+      end
+      scan file, lang, options = {}, &block
+    end
+
+    # Scan the +code+ (a string) with the scanner for +lang+.
+    #
+    # Calls scan.
+    #
+    # See CodeRay.scan.
+    def scan_stream code, lang, options = {}, &block
+      options[:stream] = true
+      scan code, lang, options, &block
+    end
+
+    # Encode a string in Streaming mode.
+    #
+    # This starts scanning +code+ with the the Scanner for +lang+
+    # while encodes the output with the Encoder for +format+.
+    # +options+ will be passed to the Encoder.
+    #
+    # See CodeRay::Encoder.encode_stream
+    def encode_stream code, lang, format, options = {}
+      encoder(format, options).encode_stream code, lang, options
+    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
+
+    # 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
+
+    # 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 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 = {}
+      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 = {}
+      Scanners[lang].new '', options
+    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
+
+  # This Exception is raised when you try to stream with something that is not
+  # capable of streaming.
+  class NotStreamableError < Exception
+    def initialize obj
+      @obj = obj
+    end
+
+    def to_s
+      '%s is not Streamable!' % @obj.class
+    end
+  end
+
+  # A dummy module that is included by subclasses of CodeRay::Scanner an CodeRay::Encoder
+  # to show that they are able to handle streams.
+  module Streamable
+  end
+
+end
+
+# Run a test script.
+if $0 == __FILE__
+  $stderr.print 'Press key to print demo.'; gets
+  # Just use this file as an example of Ruby code.
+  code = File.read(__FILE__)[/module CodeRay.*/m]
+  print CodeRay.scan(code, :ruby).html
+end