http://www.perlmonks.org?node_id=72133


in reply to Re (tilly) 1: Oh Brother.
in thread My Laptop talks to me.

I have to comment. Using symbolic references of the form $$i is stupid. It's more than stupid. You're creating unknown global variables in your script. If you're a dealing with user input, you should be socked. (Homey don't play dat!)

However, if you use symbolic references of the form ${"$package_name::$i"}, I think you're quite a bit safer. You have made sure that the global namespace is safe, especially as you're in control of $package_name. Why would you do this? Well, there's a way of implementing objects using parallel arrays instead of hashes. In certain cases, where you have a large number of instances of this class and/or you will be creating/destroying them on a regular basis, it's much faster, even with the cost of string interpolations and symbolic references.

To sum up, I don't think symbolic references are necessarily a "Bad Thing"(tm). I would actually say it's that global things are almost always bad and that the default way of creating a symbolic reference is in the global namespace.