I thought I knew perl, and then this tripped me up:

use Data::Dumper qw(Dumper);
my $a = { b => {} };
my $f = $a->{b}{c}{d}//undef;
print Dumper $a

[download]
result: 
$VAR1 = {
          'b' => {
                   'c' => {}
                 }
        };

[download]

Why does 'c' key get created during what is meant to be only an assignment operation? And under that logic, why isn't 'd' made a key of 'c' with value undef?

In reply to Arrow Operator Question by sectokia

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