Perl is not the language that most people think of when designing an application. Sure it can scrape web logs and turn X into Y in one line of code (where X and Y can be almost anything if you're Randall Schwartz), but beyond that its not used for much.
If you get in any further than a couple line script, perl just gets scary. Like today, my friend who aspires to greatness asked me if @$yy{key} was different than @{$yy{key}}.
The short answer is yes.
The long answer is that the first is an array slice dereferencing an anonymous hash in the scalar $yy. The second is dereferencing an anonymous array in the hash %yy under the key 'key'.
Perl lets you build so many layers of collections and lists that you just find yourself building these elaborate structures because they fit the data or how you want to use it. Pretty soon you're doing,
@{$res{$_->{channel_id}}{$_->{key_type}}[$k]}{qw(count z)}= @$_{qw(ct z)}
And thinking nothing of it. Ok, maybe you have to think about it a little bit because you get it wrong the first time, but a quick splash of Data::Dumper() and all is revealed.
