I have a question about variable references. If one of you guys could answer I think it would clear up a lot of things in my brain about how Perl works. I've tried R'ing The FM, but it turns out I'm too stupid or the question is too simple.

My question is: why does this work? 

use strict;

my $hash_ref=&makehash;
my %hash=%$hash_ref;

print $hash{SQUEE};

exit;

sub makehash { 

   my %sub_hash;
   $sub_hash{SQUEE}="Nny";
   return (\%sub_hash);

}

[download]
Run this and it prints "Nny". I'm confused because I thought when using "strict", variables only existed inside their blocks, so that %sub_hash would only be accessible inside &makehash. When I pass the reference to %sub_hash back from &makehash, why isn't it a reference to something that no longer exists?

I know this is very basic but a lot of my mission-critical scripts pass references (and hashes of references, etc.) and I don't like the fact that fundamentally, I have no clue what's going on. What am I missing here?

Thanks,
Kurt

In reply to What's a reference? What's a variable? What's scope? by kurt_kober

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