Good morning, and my apologies in advance for a rather long and meandering supplication.

I came across something puzzling yesterday evening; it may likely prove to be just an unremarkable example of the Fool Pattern, but anyway. I'm creating a module that fakes a particular environment, mainly by declaring big sets of global variables. It started a bit like this

package Totally::Fake;

our @ISA = qw/Exporter/;
our ($fake, @faker);

@EXPORT = qw/$fake @faker/;

[download]

The dream was that I could easily check the perl scripts I wrote for this environment using 'perl -c -MTotally::Fake -Mstrict my_script.pl', and all the variables will be there and strict won't complain.

First thing I don't understand
This didn't work. my_script.pl would refer to $fake and strict would complain. So I tried making a little test script:

use Totally::Fake;
use lib '/path/to/dev/version';
print $fake;

[download]

Second thing I don't understand:
This did work - but only because of the presence of the use lib declaration. I could add a non-existent path to @INC, so loading exactly the same version of Totally::Fake from /usr/lib/perl, and it would work, where it wouldn't without use lib. This seems really weird to me. Why should 'use lib' affect my exports?

Third thing I don't understand
So some poking and tinkering later, I happened to try 'use base qw/Exporter/' instead of 'our @ISA = qw/Exporter/' in my module ... and it finally worked how I'd like it to. Which is good, but bad. I had a look at the documentation for base. How does inheriting using base differ from declaring @ISA, so that one works here, and the other doesn't?

With thanks in advance
ViceRaid

In reply to Side effects of use-ing base (vs our @ISA) by ViceRaid

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