module ActionController::Redirecting

def _compute_redirect_to_location(options) 

def _compute_redirect_to_location(options)
  case options
  # The scheme name consist of a letter followed by any combination of
  # letters, digits, and the plus ("+"), period ("."), or hyphen ("-")
  # characters; and is terminated by a colon (":").
  when %r{^\w[\w+.-]*:.*}
    options
  when String
    request.protocol + request.host_with_port + options
  when :back
    raise RedirectBackError unless refer = request.headers["Referer"]
    refer
  else
    url_for(options)
  end.gsub(/[\r\n]/, '')
end

def _extract_redirect_to_status(options, response_status) 

def _extract_redirect_to_status(options, response_status)
  status = if options.is_a?(Hash) && options.key?(:status)
    Rack::Utils.status_code(options.delete(:status))
  elsif response_status.key?(:status)
    Rack::Utils.status_code(response_status[:status])
  else
    302
  end
end

def redirect_to(options = {}, response_status = {}) #:doc:

:doc:
behavior for this case by rescuing RedirectBackError.
When using redirect_to :back, if there is no referrer, RedirectBackError will be raised. You may specify some fallback

redirect_to { :action=>'atom' }, :alert => "Something serious happened"
redirect_to post_url(@post), :status => 301, :flash => { :updated_post_id => @post.id }
redirect_to post_url(@post), :status=> :found, :notice => "Pay attention to the road"
redirect_to post_url(@post), :alert => "Watch it, mister!"
Examples:

+alert+ and +notice+ as well as a general purpose +flash+ bucket.
It is also possible to assign a flash message as part of the redirection. There are two special accessors for commonly used the flash names

integer, or a symbol representing the downcased, underscored and symbolized description.
The status code can either be a standard {HTTP Status code}[http://www.iana.org/assignments/http-status-codes] as an

redirect_to :action=>'atom', :status => 302
redirect_to post_url(@post), :status => 301
redirect_to :action=>'atom', :status => :moved_permanently
redirect_to post_url(@post), :status => :found
Examples:

The redirection happens as a "302 Moved" header unless otherwise specified.

redirect_to :back
redirect_to articles_url
redirect_to "/images/screenshot.jpg"
redirect_to "http://www.rubyonrails.org"
redirect_to post
redirect_to :action => "show", :id => 5
Examples:

Short-hand for redirect_to(request.env["HTTP_REFERER"])
* :back - Back to the page that issued the request. Useful for forms that are triggered from multiple places.
* String not containing a protocol - The current protocol and host is prepended to the string.
* String starting with protocol:// (like http://) - Is passed straight through as the target for redirection.
* Record - The URL will be generated by calling url_for with the +options+, which will reference a named URL for that record.
* Hash - The URL will be generated by calling url_for with the +options+.

Redirects the browser to the target specified in +options+. This parameter can take one of three forms: 
def redirect_to(options = {}, response_status = {}) #:doc:
  raise ActionControllerError.new("Cannot redirect to nil!") if options.nil?
  raise AbstractController::DoubleRenderError if response_body
  self.status        = _extract_redirect_to_status(options, response_status)
  self.location      = _compute_redirect_to_location(options)
  self.response_body = "<html><body>You are being <a href=\"#{ERB::Util.h(location)}\">redirected</a>.</body></html>"
end