class Redcarpet::Render::Safe

def html_escape(string)

should be defined at the C level.
are duplicating existing code from Houdini. This method
TODO: This is far from ideal to have such method as we 
def html_escape(string)
  string.gsub(/['&\"<>\/]/, {
    '&' => '&amp;',
    '<' => '&lt;',
    '>' => '&gt;',
    '"' => '&quot;',
    "'" => '&#x27;',
    "/" => '&#x2F;',
  })
end