class CodeRay::TokensProxy

while still providing the benefits of direct streaming.
This proxy makes it possible to use the classic CodeRay.scan.encode API
The result of a scan operation is a TokensProxy, but should act like Tokens.

def each *args, &blk

Overwrite Struct#each. 
def each *args, &blk
  tokens.each(*args, &blk)
  self
end

def encode encoder, options = {}

otherwise, convert the receiver to tokens and call encoder.encode_tokens.
Call CodeRay.encode if +encoder+ is a Symbol; 
def encode encoder, options = {}
  if encoder.respond_to? :to_sym
    CodeRay.encode(input, lang, encoder, options)
  else
    encoder.encode_tokens tokens, options
  end
end

def initialize input, lang, options = {}, block = nil

Create a new TokensProxy with the arguments of CodeRay.scan. 
def initialize input, lang, options = {}, block = nil
  @input   = input
  @lang    = lang
  @options = options
  @block   = block
end

def method_missing method, *args, &blk

delegates to tokens otherwise.
Tries to call encode; 
def method_missing method, *args, &blk
  encode method.to_sym, *args
rescue PluginHost::PluginNotFound
  tokens.send(method, *args, &blk)
end

def scanner

A (cached) scanner instance to use for the scan task. 
def scanner
  @scanner ||= CodeRay.scanner(lang, options, &block)
end

def tokens

The (cached) result of the tokenized input; a Tokens instance. 
def tokens
  @tokens ||= scanner.tokenize(input)
end