Got this bit of code in a test: 

say (exists $fs4->{_structure}{'/Users/dotfiles/perl5/my_modules'}{BLA
+H}{Crap});  # BLAH  and its parent do not exist
d $fs4; # dumps the object

[download]

The dump of the object now shows this: 

### Dump from: 01-FSO_basic.t line: 35
$VAR1 = {
  '/Users/dotfiles/perl5/my_modules' => {
    'BLAH' => {}
  },

[download]

I was pretty surprised to see the path and BLAH in the output as keys. So why is 'BLAH' key getting autovivified? Second, how I work around this?

Update: This one-liner reproduces the problem for me: 

perl -MData::Dump -E ' my $fs4 = {'_structure' => {}}; exists $fs4->{_
+structure}{BLAH}{TEST}{Crap}; dd $fs4->{_structure} '

[download]

Outputs:  { BLAH => { TEST => {} } }

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