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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.
But this works fine:
use strict 'vars'; package somePkg; BEGIN { *main::foo = \@main::foo } package main; print "Foo: (@foo)\n";
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";
And this fails, as well:
use strict 'vars'; package pkg; BEGIN { *pkg::foo = \@pkg::foo } print "Foo: (@foo)\n";
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; }

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: ()

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


In reply to Creating "Lexical" Symbol Table Aliases (a la "use vars") From The Same Package by OneTrueDabe

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