my @stack;

push @stack, [ 1 .. 10 ]; # an array
push @stack, { one => 1, two => 2 }; # a hash
push @stack, 'a scalar';
push @stack, Some::Object->new;

my ($scalar, @array, %hash, $obj);

while (my $x = pop @stack) {
  if (my $type = ref $x) {
    if ($type eq 'ARRAY') {
      @array = @$x; 
    } elsif ($type eq 'HASH') {
      %hash = %$x;
    } else {
      $obj = $x;
    }
  } else {
    $scalar = $x;
  }
}