package base_class;

my $parameter_config = {
		mandatory  => {type    => 'boolean',
					   default => 0,
					   valid   => 0},
					   };

sub valid_parameter {
	my @param = @_;
	foreach (@param) {
		if (defined $parameter_config->{$_}) {
			$parameter_config->{$_}->{valid} = 1;
		} else {
			die "Parameter $_ not known";
		}
	}
	return 1;
}

sub new {
# and so on
};
1;