I'm not certain that it is a best practice, but I find that Data::Diver and eval() help out a lot when dealing with hashes and arrays.

#!/usr/bin/env perl
use Data::Dumper qw| Dumper |;
use Data::Diver qw| Dive DiveVal DiveRef DiveDie DiveError DiveClear |
+;

my $h = {
  key => 'value',
  hoh => { key => 'value' },
  hoa => [ 'a', 'b', 'c' ],
  deep => { values => { are => 'supported' } },
};

Dive($h, 'key') && warn "'key' is there";
!Dive($h, 'nokey') && warn "'nokey' is not there";
warn "notice 'nokey' was not created";
warn Dumper $h;

warn "Values are: " . join(', ', eval {@{Dive($h, 'hoa')}});
warn "No errors for non arrays: " . join(', ', eval {@{Dive($h, 'empty
+')}});
warn "Deep values: ". Dive($h, qw| deep values are |);
!Dive($h, qw| deep values that is not there |) && warn "Missing Deep v
+alues are safe";


__END__
'key' is there at ./test.pl line 12.
'nokey' is not there at ./test.pl line 13.
notice 'nokey' was not created at ./test.pl line 14.
$VAR1 = {
          'deep' => {
                      'values' => {
                                    'are' => 'supported'
                                  }
                    },
          'hoa' => [
                     'a',
                     'b',
                     'c'
                   ],
          'hoh' => {
                     'key' => 'value'
                   },
          'key' => 'value'
        };
Values are: a, b, c at ./test.pl line 17.
No errors for non arrays:  at ./test.pl line 18.
Deep values: supported at ./test.pl line 19.
Missing Deep values are safe at ./test.pl line 20.
[download]

Some of those are still not beautiful ( especially array dereference ), but I find it a clean way to deal with hashes, as it already implements the autovivification and error handling logic.

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