in reply to My globals are visable; but undef'ed

Variables introduced using my $varname are lexically scoped and not bound to any package.

You probably want to use our $varname instead, if you really want package variables. See also my our and possibly local (but note that local doesn't do what you might think).

Update: the reason you can "see" the globals using $main::varname is that specifying an explicit package name refers to the package variable whether it's been declared or not. In other words, you're referring to $main::varname, but your lexical $varname isn't the same variable; it just has the same name (but it's not bound to the main package).

"What should it profit a man, if he should win a flame war, yet lose his cool?"

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Re^2: My globals are visable; but undef'ed
by BrowserUk (Patriarch) on Jul 31, 2008 at 22:15 UTC

    For counterpoint, using our is perfect for the OP's task.

    By lexically scoping all his wide-scoped package vars, and reducing their visibility to just those places where they are used--prior to splitting the monolithic script into modules--it becomes far easier to identify which variables have to be passed to what subroutines. And that makes the second stage of the process, passing them as parameters, far easier.

    As an intermediate step in a refactoring process, lexically scoping the globals is far better than C&Ping the same a huge block of global declarations at the top of every module.

    Lexically scope them in the big file first. Make sure everything still works. Split the function into modules--perhaps using the new found knowledge of what routines are dependant upon which globals as an aid to deciding what should go with what--and check again everything still works. Then set about passing those variables through parameters. A totally sane and logical refactoring process.

    And for singletons they are perfect too. Even if you do leave them declared at the package scope level.

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Re^2: My globals are visable; but undef'ed
by tilly (Archbishop) on Jul 31, 2008 at 19:26 UTC
    Actually you probably shouldn't use our, see Why is 'our' good? for my explanation of why I don't like it when you're sharing data between modules.
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      Well, there are enough cases where package variables are the only thing that works (mostly cases where perl insists on making package vars special). But your complaint isn't about that, exactly. Me, I just use our as a neater replacement for vars (IOW, I practically always just use our at the top of the script - and I prefer it over vars for that just because it looks better).

      "What should it profit a man, if he should win a flame war, yet lose his cool?"
[reply]
        I grant that it looks prettier, but if you're going to be sharing variables between scripts, it is distinctly worse.

        Within a script it doesn't matter which you use, but it is probably better to use my instead.

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