Same hash, two ways to access: hai eq hai
Original hash: {
  'somekey' => 'someval',
  'o' => 'hai'
}
Hash deleting key o: {
  'somekey' => 'someval'
}
Use of uninitialized value in print at /Users/moo/Desktop/pm.pl line 17.
Print it directly (unintialized now): o => 
Hash after moving stuff around: {
  'new_key' => {
                 'o' => 'hai',
                 'sub_key' => 'new value'
               },
  'somekey' => 'someval'
}
Perl data structures are *flexible* {
  'subroutine' => sub { "DUMMY" },
  'fancy_data' => [
                    'one',
                    {
                      'two' => 'is a hash(ref)'
                    },
                    [
                      'another',
                      'array'
                    ],
                    'last'
                  ],
  'somekey' => 'someval',
  'as' => {
            'deep' => {
                        'as' => {
                                  'array_ref' => [
                                                   'one',
                                                   'two'
                                                 ],
                                  'you' => 'please'
                                }
                      }
          },
  'new_key' => {
                 'o' => 'hai',
                 'sub_key' => 'new value'
               }
}
Excecuting code ref through data...OHAI!