When trying to use typeglob for aliasing purposes, I ran into a strange behavior. I wonder if someone could explain the logic behind.

The following code (trying to access the hash directly as %foo) does not work:

use strict;
use warnings;
my $hashref = { "key" => "value" };
local *foo = $hashref;
printf("keys=%d\n", scalar(keys(%foo)));
[download]

I get both 'Variable "%foo" is not imported' (which I find weird) and 'Global symbol "%foo" requires explicit package name' (which explains the problem). So far so good.

Attempting to use "my", the code now executes (with a warning: 'Name "main::foo" used only once: possible typo') but I do not get the expected result:

use strict;
use warnings;
my $hashref = { "key" => "value" };
my %foo;
local *foo = $hashref;
printf("keys=%d\n", scalar(keys(%foo)));
# prints: keys=0
[download]

Using "our" instead of "my", I do get the expected result:

use strict;
use warnings;
my $hashref = { "key" => "value" };
our %foo;
local *foo = $hashref;
printf("keys=%d\n", scalar(keys(%foo)));
# prints: keys=1
[download]

Could someone please explain why the "my" version is good enough to make Perl happy while still returning an unexpected result?

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