Singleton question

[vippagunta]

Hi,

I have a Utility package which reads a couple of config files and does some other things like initializing log4perl etc. Other parts of my program(i.e. my other packages) need access to the contents of the config file and I don't want to pass the reference to my Utility package to other packages. So, I am thinking I need a Singleton. Is this the right approach?

Thanks,
Srini.

[dHarry]

A logging service is a classic example of a Singleton. What confuses me is the "utility package". Maybe a Toolbox Singleton is a better way. See Use your singletons wisely for an interesting discussion on the topic. (Beware that these are java examples.)

Cheers,

Harry

[pajout]

Yes, in my opinion. For instance (just motivation code...):

package My::Utils;

my %instance;

sub read_conf {
  #fills %instance
}

sub value {
  my ($name, $new_val) = @_;
  if (2 == @_) { #new value passed
    $instance{$name} = $new_val;
  }
  return $instance{$name};
}

package My::Something
use My::Utils;
print My::Utils::value("something_configured");

but I prefer to really create instance of the object, and then just call $utils_instance->value("something"). Of course, it needs a little different My::Utils.