How to validate Markdown?

protected:

def validate
  bc = BlueCloth.new(your_markdown_string_attribute)
  begin
    bc.to_html
  rescue
    errors.add(:your_markdown_string_attribute, 'has invalid markdown syntax')
  end
end

begin
  require "rdiscount"
  BlueCloth = RDiscount
rescue LoadError
  # BlueCloth is still the our fallback,
  # if RDiscount is not available
  require 'bluecloth'
end