LWP::MemberMixin - Member access mixin class
A mixin class to get methods that provide easy access
to member variables in the %$self.
Ideally there should be better Perl langauge support for this.
Internal method to get/set the value of member variable
$elem. If $val is defined it is used as the new value for the member variable. If it is
undefined the current value is not touched. In both cases the previous
value of the member variable is returned.