In perl, if we want to get the key/value pairs of hash, you can use the following code.

use strict;
use warnings;

# initializing hash with three four-value pairs, among those two are h
+aving inner hashes ( Numerals, Alpha ) which have three key-value pai
+rs in-built
my %hash = ( 'Numerals' => {  
    '1'  => 'One',
    '2' => 'Two',
    '3' => 'Three',
    }, 'Alpha' => {
    'A' => 'Apple',
    'B' => 'Ball',
    'C' => 'Cat'
    },
    'I' => 'Roman One',
    'II' => 'Roman Two'
);<br/>

# for getting key-value pairs of above hash
foreach(keys%$hash) {
  # by default key stored in $_ as per above foreach statement
   # checks whether value of hash is another hash
   if(ref($hash{$_}) eq 'HASH') {
        # iterate the keys set of inner hash
        foreach my $inner_key (keys%{$hash{$_}})    { 
            # printing key and value of inner hash
            print "Key:$inner_key and value:$hash{$_}{$inner_key}\n"; 
        }
    } else {
        print "Key: $_ and Value: $hash{$_}\n" 
    }
}

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In reply to Re: Iterate over a perl nested hash data structure by nvivek
in thread Iterate over a perl nested hash data structure by NewLondonPerl1

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