If there is no package, it's ::, or main::. But that's the definition of "global" in Perl - a package variable is visible everywhere, even if you have to explicitly specify the package, while a lexical is not. It's similar to C++'s namespaces - sure, you can have more than one global variable, as long as they're in different namespaces / packages, but they're still global.

The danger in do is just that Perl 5 has conventions. And those conventions are about useing modules, not evaling file contents. And because these are the conventions, that's what people are used to. When you buck those conventions, you introduce an error-prone area where nuances of the implementation (which are generously documented, but who looks at documentation? ;->) can bite you. For example, it seems common that people expect that do FILE will import lexicals (despite the docs). But I've not yet seen someone assume that from a use MODULENAME that has, as per convention, a package declaration at the top.

That's not to say "never use do FILE" - just be sure you know what you're doing when you do so. It's an uncommon idiom, and, usually, a more common idiom would not only serve the same purpose, but be more maintainable. Even though I can't think of a good reason to use do FILE over either a proper module or a config file (depending on what the use is) doesn't mean I'm discounting the possibility. ;-)

In reply to Re^3: strict/do question by Tanktalus
in thread strict/do question by dch

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