Rakefile

task :default => :build

task :build do
  contents = File.read("README.md.docu")

  reading_assertion = false
  reading_example = false
  current_example = nil
  current_assertion = nil

  contents.lines.each do |line|
    current_example ||= []
    current_assertion ||= []

    if line.strip == ":example:"
      reading_example = true
      reading_assertion = false
    elsif line.strip == ":assertion:"
      reading_example = false
      reading_assertion = true
    elsif line.strip == ":end:"
      reading_example = false
      reading_assertion = false

      example = current_example.join("\n")
      assertion = current_assertion.join("\n").gsub("#=>", "").strip
      result = eval(example).to_s.strip
      if result != assertion
        raise "Assertion does not match example. Expected \"#{result}\" to equal \"#{assertion}\"."
      end
      current_example = []
      current_assertion = []
    else
      current_example << line if reading_example
      current_assertion << line if reading_assertion
    end
  end
end