use strict;
use warnings;
my $label1 = 'L1';
my $label2 = 'L2';
my %hash;
@hash{'a' .. 'h'} = (
    {$label1 => 1 },
    {$label1 => 2 },
    {$label2 => 3 },
    {$label1 => 4 },
    {$label2 => 5 },
    {$label1 => 6 },
    {$label2 => 7 },
    {$label1 => 8 },
);
while ( my( $key,$subhash ) = each %hash) {
    print "$key: $subhash->{$label1}\n" if exists $subhash->{$label1};
}
[download]

a: 1
d: 4
h: 8
b: 2
f: 6
[download]

indeed!

> I want to print all the labels and values for each of a .. h

  DB<103> @hash{$_} = {x=>$x++,y=>$x++} for a..h
 => ""

  DB<112> while ( my ($k1,$v1) = each %hash ) {
            while ( my ($k2,$v2) = each %$v1 ) {
              print "$k1 - $k2 -$v2\n"
            }
          }
e - y -25
e - x -24
a - y -17
a - x -16
d - y -23
d - x -22
... # and so on
[download]

But are you looking for Data::Dumper ?

UPDATE

  DB<106> print Dumper \%hash
$VAR1 = {
          'e' => {
                   'y' => 9,
                   'x' => 8
                 },
          'a' => {
                   'y' => 1,
                   'x' => 0
                 },
          'd' => {
                   'y' => 7,
                   'x' => 6
                 },
          'c' => {
                   'y' => 5,
                   'x' => 4
                 },
...
[download]

FWIW I prefer Data::Dump or YAML¹, but Data::Dumper is core.

¹) interesting Module::Build::YAML was first released with perl 5.009004

UPDATE YAML

  DB<106> use YAML::Tiny
 => 0

  DB<107> Dump(\%hash) 
---
a:
  x: 16
  y: 17
b:
  x: 18
  y: 19
c:
  x: 20
  y: 21
d:
  x: 22
  y: 23
...
[download]

doing it like this:

my @array = qw( FirstName     LastName     MiddleName     LegalInd 
            DateOfBirth     Sex         Race         Ethnicity
             Height         Weight         Build         Eyes 
            Hair         SocSecNo     MaritalStatus    PlaceOfBirthCit
+y
            PlaceOfBirthState         AddressType    DfAdate
            StreetNumber     StreetName     StreetType    City 
            State         Zip );

    for (@array) {    
        $xml_writer->dataElement("$_"     => $t{A}{$_});    
    }
[download]

> doing it like this

Doing what?

(Do you speak English?)

Look I've shown you code iterating thru the whole structure.

If you can't express your problem in proper words, you are still free to adapt the two nested loops to your needs.

Cheers Rolf

( addicted to the Perl Programming Language)