How to iterate through Hash (of Hashes) in Perl?

Question

I have Hash where values of keys are other Hashes.

Example: {\'key\' => {\'key2\' => {\'key3\' => \'value\'}}}

How can I iterate throug

Answer 1

If you are using perl as a "CPAN interpreter" then in addition to Data::Visitor and Data::Deep there is the super simple Data::Traverse:

use Data::Traverse qw(traverse);

my %test_hash = (
  q => [qw/1 2 3 4/],
  w => [qw/4 6 5 7/],
  e => ["8"],
  r => { 
         r => "9"  ,
         t => "10" ,
         y => "11" ,
      } ,
);

traverse { next if /ARRAY/; print "$a => $b\n" if /HASH/ && $b > 8 } \%test_hash;

Output:

t => 10
y => 11

$a and $b are treated as special variables here (as with sort()) while inside the traverse() function. Data::Traverse is a very simple but immensely useful module with no non-CORE dependencies.