membermixin.pm

美国CMU大学开发的操作系统健壮性评测软件

#
# $Id: MemberMixin.pm,v 1.1 1999/07/21 19:12:32 kraven Exp $

package LWP::MemberMixin;

=head1 NAME

LWP::MemberMixin - Member access mixin class

=head1 SYNOPSIS

 package Foo;
 require LWP::MemberMixin;
 @ISA=qw(LWP::MemberMixin);

=head1 DESCRIPTION

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.

There is only one method provided:

=over 4

=item _elem($elem [, $val])

Internal method to get/set the value of member variable
C<$elem>. If C<$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.

=back

=cut

sub _elem
{
    my($self, $elem, $val) = @_;
    my $old = $self->{$elem};
    $self->{$elem} = $val if defined $val;
    return $old;
}

1;