class Rouge::Lexers::Escape

def initialize(*)
  super
  @start = string_option(:start) { '<!' }
  @end = string_option(:end) { '!>' }
  @lang = lexer_option(:lang) { PlainText.new }
end

def stream_tokens(str, &b)
  stream = StringScanner.new(str)
  loop do
    if stream.scan(to_start_regex)
      puts "pre-escape: #{stream[1].inspect}" if @debug
      @lang.continue_lex(stream[1], &b)
    else
      # no more start delimiters, scan til the end
      @lang.continue_lex(stream.rest, &b)
      return
    end
    if stream.scan(to_end_regex)
      yield Token::Tokens::Escape, stream[1]
    else
      yield Token::Tokens::Escape, stream.rest
      return
    end
  end
end

def to_end_regex
  @to_end_regex ||= /(.*?)(#{Regexp.escape(@end)})/m
end

def to_start_regex
  @to_start_regex ||= /(.*?)(#{Regexp.escape(@start)})/m
end