{ 
   one => [ [ 1, 2 ], 3 ];
   ...
}

##</code><code>##

{ 
   one => [ [ [ 1, 2 ], 3 ], 4 ];
   ...
}

##</code><code>##

{ 
    one => '1 2 3 4',
    ...
}

##</code><code>##

#!/usr/bin/perl -w
 use strict;
 use Data::Dumper;

 my %h1 = ( "one"   => 1, "two"   => 2, "three" => 3,   );
 my %h2 = (  "four"  => 4, "five"  => 5, "six"   => 6, "one"   => 11111, );
 foreach my $x ( keys %h2 ){
     $h1{ $x } .=  ' ' . $h2{ $x };
 }
 print Dumper (\%h1);

##</code><code>##

#!/usr/bin/perl -w
 use strict;
 use Data::Dumper;

 my %h1 = ( "one"   => 1, "two"   => 2, "three" => 3,   );
 my %h2 = (  "four"  => 4, "five"  => 5, "six"   => 6, "one"   => 11111, );
 foreach my $x ( keys %h2 ){
     $h1{ $x } .=  $; . $h2{ $x };
 }
 print Dumper (\%h1);