I do not find the fact that i include a "use" declaration for new functionality suprising, this is i what i normally expect and want.

sub load {
    my ($self, $filename) = @_;
    open (LOGGERS, "< " . $filename);
    my ($line);
    while ($line = <LOGGERS>) {
    chomp $line; 
    if (!$line) { last;}
    my @parms = split /:/, $line;
    my $loggertyp = shift @parms;
    my $logger = ${loggertyp}->new();
        $logger->systemname($self->systemname);
        $logger->subject($self->subject);
    while (@parms) {
        my $parmtyp = shift @parms; 
        my $parmvalue = shift @parms;
        ${logger}->${parmtyp}($parmvalue);
    } 
    $self->loggers($logger);
    }
    close(LOGGERS);
}
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It actually knows nothing about "functionality" it makes available.

In this context it would be a great thing, if i just could write a new perl module, change the file and the tell the daemon through some signal, to newly load the file and the "daemon" executes new functionality,granteed the whole thing is well tested etc. With the "use" declarations, i additionally have to stop the "daemon" and change the source code of this module. So that's the reason, that in this context, i would prefer not be be explicit.

This is your problem here:

my $logger = ${loggertyp}->new();
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If you're gonna call new, you're gonna have to ensure that the package is loaded. See how the LWP moudules do it for the various protocol handlers. It's a mere matter of coding up a proper require dynamically. No big deal, but you have to do it, true.

Or, you can add something like the following subroutine (untested):

sub UNIVERSAL::AUTOLOAD {
  my ($pack, $meth) = $AUTOLOAD =~ /(.*)::(.*)/;
  die "do you really want me to pull in $pack for $meth?\n" unless $me
+th eq "new";
  eval "require $pack"; die $@ if $@;
  die "$pack didn't define $meth" unless defined &$AUTOLOAD;
  goto &$AUTOLOAD;
}
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-- Randal L. Schwartz, Perl hacker

Thanx, i think got it:

With UNIVERSAL::AUTOLOAD one can intercept calls to a perl object, which have failed

With "require" one can dynamically "use" modules, depending for example on some input, like in my case reading the Objectname from the input

Really neat stuff, but i agree that most application would'nt want or need to use this stuff...

I wonder, how perl compares here with other languages....

But anyway, thanx for the help

Chris