In Perl, globals are not exported by default anywhere, at any time (including functions and methods). In fact, nothing is. You need to explicitly export them before they can be imported into any other module/package that uses a Perl file, so that safeguard is built in.

In other words, as I said in my last post, things are file-based scope. Anything in another file that uses a different file does not have implicit access (ie. namespaces won't be clobbered) unless that is specifically and explicitly configured.

You can include other Perl files to your heart's content, and unless you explicitly export things (from the included file (in Python, an import), you'll never be able to see them within your current namespace.

Also, useing a Perl file does not execute it, so any executable code you have in a Perl file will not be run when including it into another Perl file. That means that you can have main() code anywhere in a Perl file, even non-scoped (file-level global), that will not be executed or evaluated (into) when including said file in another file.

I digress a bit. There *are* ways around this, but I believe my fellow monks would agree with me that those are round-about ways, and most definitely not common, standard practice that you'd find in any remotely reasonable example unless you were outright looking for such a way.

In reply to Re^3: Using guards for script execution? by stevieb
in thread Using guards for script execution? by R0b0t1

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