OzzyOsbourne has asked for the wisdom of the Perl Monks concerning the following question:
I looked at the docs, looked at some threads, delved into the CB, and consulted the magic 8 ball, but I still can't seem to get my head around the answer to:
What is the difference between my, use vars, and our?
Most answers seemed vague, or I just didn't understand. The most worrysome answer was "Outlook not so good" from the magic 8-ball. I'm an NT admin. I know about Outlook not so good. Tell me about Perl scope, 8-ball. Perl scope!
What I think I know:
- my declares variables in lexical scope. Yup, got it.
- use vars allows you to declare global variables, and refer to $package::$foo as $foo. Right on.
- and our is the same as use vars but with lexical scope. A globally lexically thingy. OK.
So on line 4 or 5, before any blocks, I declare my $foo. It acts with a lexical scope of the entire script. It acts sort of like a global variable.
What if I put our $foo in the same place. Do I get the same effect? What if I put use vars $foo?
My questions:
- Is there any difference between declaring variables at the beginning of scripts with my or our? Won't their scope be the same?
- Is there a reason to use one or the other in this situation
See this example. Look at %TOC. Should it be my or our?
Thanks for your help.