module Sinatra::Templates

def render_builder(template, data, options, &block)
  xml = ::Builder::XmlMarkup.new(:indent => 2)
  if data.respond_to?(:to_str)
    eval data.to_str, binding, '<BUILDER>', 1
  elsif data.kind_of?(Proc)
    data.call(xml)
  end
  xml.target!
end