I assume the line that's confusing you is the following: 
@A{keys %r} = keys %r;

[download]
Essentially, it's doing the same thing as the following code, which should be a lot easier to understand: 
foreach $key (keys %r) {
    $A{ $key } = $key;
}

[download]

In reply to Re: strange looking code by kilinrax
in thread strange looking code by Jonathan

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