如何在Rails 3中使用markdown自动渲染部分？

gem 'redcarpet'

require 'redcarpet'

class MarkdownRenderer < Redcarpet::Render::HTML
  def block_code(code, language)
    # 自定义代码块的渲染方式
  end
end

module ApplicationHelper
  def markdown(text)
    renderer = MarkdownRenderer.new(filter_html: true, hard_wrap: true)
    options = {
      autolink: true,
      no_intra_emphasis: true,
      fenced_code_blocks: true,
      lax_html_blocks: true,
      strikethrough: true,
      superscript: true
    }
    markdown = Redcarpet::Markdown.new(renderer, options)
    markdown.render(text).html_safe
  end
end

<%= markdown("# Hello, World!") %>