So I don't know if this belongs in SoPW or Meditations, but I stumbled across the following (what I would call) inconsistency, and wondered if anybody had an explanation...

This does not work:

   use strict 'vars';

   BEGIN { *main::foo = \@main::foo }
   print "Foo: (@foo)\n";

   __OUTPUT__

   Variable "@foo" is not imported at foo.pl line 10.
   Global symbol "@foo" requires explicit package name at foo.pl line 
+10.
   foo.pl had compilation errors.
[download]

But this works fine:

   use strict 'vars';

   package somePkg;
      BEGIN { *main::foo = \@main::foo }

   package main;
      print "Foo: (@foo)\n";
[download]

Somewhat interestingly, this seems to work okay, too:

   use strict 'vars';

   # We're already in package main
   BEGIN { *pkg::foo = \@pkg::foo }

   package pkg;
      print "Foo: (@foo)\n";
[download]

And this fails, as well:

   use strict 'vars';

   package pkg;
      BEGIN { *pkg::foo = \@pkg::foo }
      print "Foo: (@foo)\n";
[download]

I noticed that running "perl -MO=Deparse" on the last snippet, above, shows the symbol table manipulation being (*cough*) "optimized" (*cough*) thusly:

    package pkg;
    sub BEGIN {
        *foo = \@foo;
    }
[download]

Perhaps that's why "strict" doesn't allow me to access the unqualified "@foo" directly? Because -- since it's not in a different package -- something, somewhere, isn't creating the corresponding lexical alias? *Shrug*

Finally, this is mostly the same as number 2, above, which also works, but in the fewest lines:

   use strict 'vars';

   BEGIN { package pkg; *main::foo = \@main::foo }
   print "Foo: (@foo)\n";

   __OUTPUT__

   Foo: ()
[download]

PS - Before you say "Just use 'our'" ...

Yes, I know. There's More Than One Way To Do It, and I'm MORE curious about the underlying question of why THIS way happens to fail.

Thanks! :-D

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