class WWW::Mechanize::Util

def build_query_string(parameters)
  parameters.map { |k,v|
    k &&
      [WEBrick::HTTPUtils.escape_form(k.to_s),
        WEBrick::HTTPUtils.escape_form(v.to_s)].join("=")
  }.compact.join('&')
end

def html_unescape(s)
  return s unless s
  s.gsub(/&(\w+|#[0-9]+);/) { |match|
    number = case match
    when /&(\w+);/
      Mechanize.html_parser::NamedCharacters[$1]
    when /&#([0-9]+);/
      $1.to_i
    end
    number ? ([number].pack('U') rescue match) : match
  }
end