This is used to get/set the raw content and it is inherited from the
C<HTTP::Message> base class.  See L<HTTP::Message> for details and
other methods that can be used to access the content.

=item $r->decoded_content( %options )

This will return the content after any C<Content-Encoding> and
charsets have been decoded.  See L<HTTP::Message> for details.

=item $r->request

=item $r->request( $request )

This is used to get/set the request attribute.  The request attribute
is a reference to the the request that caused this response.  It does
not have to be the same request passed to the $ua->request() method,
because there might have been redirects and authorization retries in
between.

=item $r->previous

=item $r->previous( $response )

This is used to get/set the previous attribute.  The previous
attribute is used to link together chains of responses.  You get
chains of responses if the first response is redirect or unauthorized.
The value is C<undef> if this is the first response in a chain.

=item $r->status_line

Returns the string "E<lt>code> E<lt>message>".  If the message attribute
is not set then the official name of E<lt>code> (see L<HTTP::Status>)
is substituted.

=item $r->base

Returns the base URI for this response.  The return value will be a
reference to a URI object.

The base URI is obtained from one the following sources (in priority
order):

=over 4

=item 1.

Embedded in the document content, for instance <BASE HREF="...">
in HTML documents.

=item 2.

A "Content-Base:" or a "Content-Location:" header in the response.

For backwards compatibility with older HTTP implementations we will
also look for the "Base:" header.

=item 3.

The URI used to request this response. This might not be the original
URI that was passed to $ua->request() method, because we might have
received some redirect responses first.

=back

If none of these sources provide an absolute URI, undef is returned.

When the LWP protocol modules produce the HTTP::Response object, then
any base URI embedded in the document (step 1) will already have
initialized the "Content-Base:" header. This means that this method
only performs the last 2 steps (the content is not always available
either).

=item $r->filename

Returns a filename for this response.  Note that doing sanity checks
on the returned filename (eg. removing characters that cannot be used
on the target filesystem where the filename would be used, and
laundering it for security purposes) are the caller's responsibility;
the only related thing done by this method is that it makes a simple
attempt to return a plain filename with no preceding path segments.

The filename is obtained from one the following sources (in priority
order):

=over 4

=item 1.

A "Content-Disposition:" header in the response.  Proper decoding of
RFC 2047 encoded filenames requires the C<MIME::QuotedPrint> (for "Q"
encoding), C<MIME::Base64> (for "B" encoding), and C<Encode> modules.

=item 2.

A "Content-Location:" header in the response.

=item 3.

The URI used to request this response. This might not be the original