module HTTP::Chainable

def timeout(klass, options = {})
  if klass.is_a? Hash
    options = klass
    klass   = :per_operation
  end
  klass = case klass.to_sym
          when :null          then HTTP::Timeout::Null
          when :global        then HTTP::Timeout::Global
          when :per_operation then HTTP::Timeout::PerOperation
          else raise ArgumentError, "Unsupported Timeout class: #{klass}"
          end
  [:read, :write, :connect].each do |k|
    next unless options.key? k
    options["#{k}_timeout".to_sym] = options.delete k
  end
  branch default_options.merge(
    :timeout_class => klass,
    :timeout_options => options
  )
end