I was working on a project and ran into this "unexpected behavior", and was wondering if some monks would discuss the finer points of adding and deleting hash keys. As a simplified example,in the following script, if I delete $info{'level_b'}, then try to delete $info{'level_b'}{2}{'name'}, $info{'level_b'}{2} gets created by the second "delete". It dosn't seem right to me. Does this mean you have to delete the most deeply nested keys first, and work your way out? Is there some way to deal with this behavior. I would have expected the second delete to just fail. TIA 
#!/usr/bin/perl
use warnings;
use strict;
use Data::Dumper;

my %info = (
     level_a => {
                1 => {
                  name  => "a",
                  loc   => "b",
                  },
               },

     level_b => {
                2 => {
                  name  => "c",
                  loc   => "d",

                  },
                },

     level_c => {
                3 => {
                  name  => "e",
                  loc   => "f",
                  }
               }
);


delete $info{'level_b'} or warn $!;

#the following delete creates $info{'level_b'}{2} ??
delete $info{'level_b'}{2}{'name'} or warn $!;

#delete $info{'level_b'} or warn $!; #works fine 

print Dumper(%info);

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In reply to deleting a hash key can create one? by zentara

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