The Tokens class represents a list of tokens returnd from a Scanner.
A token is not a special object, just a two-element Array consisting of
the token text (the original source of the token in a String) or a token action (#begin_group, #end_group, #begin_line, #end_line)
the token kind (a Symbol representing the type of the token)
A token looks like this:
['# It looks like this', :comment] ['3.1415926', :float] ['$^', :error]
Some scanners also yield sub-tokens, represented by special token actions, namely #begin_group and end_group.
The Ruby scanner, for example, splits “a string” into:
[ [:begin_group, :string], ['"', :delimiter], ['a string', :content], ['"', :delimiter], [:end_group, :string] ]
Tokens is the interface between Scanners and Encoders: The input is split and saved into a Tokens object. The Encoder then builds the output from this object.
Thus, the syntax below becomes clear:
CodeRay.scan('price = 2.59', :ruby).html
# the Tokens object is here -------^
See how small it is? ;)
Tokens gives you the power to handle pre-scanned code very easily: You can convert it to a webpage, a YAML file, or dump it into a gzip'ed string that you put in your DB.
It also allows you to generate tokens directly (without using a scanner), to load them from a file, and still use any Encoder that CodeRay provides.
The Scanner instance that created the tokens.
Undump the object using Marshal.load, then unzip it using CodeRay::GZip.gunzip.
The result is commonly a Tokens object, but this is not guaranteed.
# File lib/coderay/tokens.rb, line 201 def Tokens.load dump dump = GZip.gunzip dump @dump = Marshal.load dump end
# File lib/coderay/tokens.rb, line 207 def begin_group kind; push :begin_group, kind end
# File lib/coderay/tokens.rb, line 209 def begin_line kind; push :begin_line, kind end
Return the actual number of tokens.
# File lib/coderay/tokens.rb, line 181 def count size / 2 end
Dumps the object into a String that can be saved in files or databases.
The dump is created with Marshal.dump; In addition, it is gzipped using CodeRay::GZip.gzip.
The returned String object includes Undumping so it has an undump method. See ::load.
You can configure the level of compression, but the default value 7 should be what you want in most cases as it is a good compromise between speed and compression rate.
See GZip module.
# File lib/coderay/tokens.rb, line 174 def dump gzip_level = 7 dump = Marshal.dump self dump = GZip.gzip dump, gzip_level dump.extend Undumping end
Encode the tokens using encoder.
encoder can be
a symbol like :html oder :statistic
an Encoder class
an Encoder object
options are passed to the encoder.
# File lib/coderay/tokens.rb, line 66 def encode encoder, options = {} encoder = Encoders[encoder].new options if encoder.respond_to? :to_sym encoder.encode_tokens self, options end
# File lib/coderay/tokens.rb, line 208 def end_group kind; push :end_group, kind end
# File lib/coderay/tokens.rb, line 210 def end_line kind; push :end_line, kind end
Redirects unknown methods to encoder calls.
For example, if you call tokens.html, the HTML encoder is used
to highlight the tokens.
# File lib/coderay/tokens.rb, line 80 def method_missing meth, options = {} encode meth, options rescue PluginHost::PluginNotFound super end
Split the tokens into parts of the given sizes.
The result will be an Array of Tokens objects. The parts have the text size specified by the parameter. In addition, each part closes all opened tokens. This is useful to insert tokens betweem them.
This method is used by @Scanner#tokenize@ when called with an Array of source strings. The Diff encoder uses it for inline highlighting.
# File lib/coderay/tokens.rb, line 95 def split_into_parts *sizes parts = [] opened = [] content = nil part = Tokens.new part_size = 0 size = sizes.first i = 0 for item in self case content when nil content = item when String if size && part_size + content.size > size # token must be cut if part_size < size # some part of the token goes into this part content = content.dup # content may no be safe to change part << content.slice!(0, size - part_size) << item end # close all open groups and lines... closing = opened.reverse.flatten.map do |content_or_kind| case content_or_kind when :begin_group :end_group when :begin_line :end_line else content_or_kind end end part.concat closing begin parts << part part = Tokens.new size = sizes[i += 1] end until size.nil? || size > 0 # ...and open them again. part.concat opened.flatten part_size = 0 redo unless content.empty? else part << content << item part_size += content.size end content = nil when Symbol case content when :begin_group, :begin_line opened << [content, item] when :end_group, :end_line opened.pop else raise ArgumentError, 'Unknown token action: %p, kind = %p' % [content, item] end part << content << item content = nil else raise ArgumentError, 'Token input junk: %p, kind = %p' % [content, item] end end parts << part parts << Tokens.new while parts.size < sizes.size parts end
Turn tokens into a string by concatenating them.
# File lib/coderay/tokens.rb, line 72 def to_s encode CodeRay::Encoders::Encoder.new end