module Nokogiri

def parse(string, url = nil, encoding = nil, options = nil)
  if string.respond_to?(:read) ||
      /^\s*<(?:!DOCTYPE\s+)?html[\s>]/i.match?(string[0, 512])
    # Expect an HTML indicator to appear within the first 512
    # characters of a document. (<?xml ?> + <?xml-stylesheet ?>
    # shouldn't be that long)
    Nokogiri.HTML4(
      string,
      url,
      encoding,
      options || XML::ParseOptions::DEFAULT_HTML,
    )
  else
    Nokogiri.XML(
      string,
      url,
      encoding,
      options || XML::ParseOptions::DEFAULT_XML,
    )
  end.tap do |doc|
    yield doc if block_given?
  end
end