This seems very strange to me, but it works: 

#!/usr/bin/perl

use strict;
use warnings;

my  $n1 = 10;
our $n2 = 20;

sub foo {
    $n1++;  # ???
    $n2++;
}

print "$n1\n";
print "$n2\n";
foo;
print "$n1\n";
print "$n2\n";

[download]
prints 
10
20
11
21

[download]

I would expect the $n2 package global to work fine in the above code, and it does. But how does perl allow foo() get away with referring to $n1 like that? When parsing sub foo, shouldn't perl say, "Nope. There's no local here named $n1, and no package global named $n1, so I don't see which $n1 you're talking about."?

BTW, I can see just fine how the following works: 

my $bar = 2;

{
    print "Hi \$bar ($bar), good to see you.\n";
}

[download]
because that's just how scoping works. But it looks to me like there's supposed to be a distinction between that and the way foo() above is doing business... (confused)

In reply to Using an "outer" lexical in a sub? by cornballer

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