class type auth_session =Anobject..end
auth_session represents an authenticated sessionmethod auth_scheme : stringmethod auth_domain : string listmethod auth_realm : stringmethod auth_user : stringmethod auth_in_advance : boolmethod authenticate : http_call -> (string * string) listauthorization.)
 If the call is authenticated in advance, it does not contain
 any authentication information. If the call is authenticated
 in reaction to a 401 status, the response header contains 
 the www-authenticate field(s).
method invalidate : http_call -> booltrue if another authentication should
 be started immediately.
 Note: By returning true the session can indicate a "stale"
 condition in the sense of RFC 2617.
