So there I was, happily rolling along, writing my class, and using an array ref as my underlying data structure. I then wrote another method: 
sub another_method {
    my ($self, $magic_val) = @_;
    $$[MAGIC_VALS]{$magic_val} = 1;
}

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and ran it. There were no compile-time or run-time errors, but the logic did not work. Can you spot the problem? That's right: it should be $$self[MAGIC_VALS]{$magic_val} instead! What is this magical @$? Perl does not complain about it and will happily use this array: 
use strict;
use warnings;

$$[0] = 1;
$$[1] = 'dude!';
print "@$", "\n";     # Prints "1 dude!"

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It's not in perlvar... What's up with this variable?

In reply to Why did @$ variable bite me in the ass? by dmitri

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