$ perl -MData::Dump  -E '$fs4={_structure=>{"/Users/dotfiles/perl5/my_modules"=>{}}};my $b= $fs4->{_structure}{"/Users/dotfiles/perl5/my_modules"};say (exists $b->{BLAH} and exists $b->{BLAH}{crap}); say dd( $fs4)'

##</code><code>##

{ _structure => { "/Users/dotfiles/perl5/my_modules" => {} } }
1