use XML::Simple;
$xml = new XML::Simple( ForceArray => [qw( product color )]);
$file = $xml -> XMLin('./prod.xml', );

foreach $products (@{$file->{product}})	{
    print "Widget: " . $products->{title} ." \n";
    print "Rating: " . $products->{rating} . "\n";
    print "  Cost: " . $products->{cost} . "\n";
    print "Colors: " . (join ", ", @{$products->{color}})."\n\n";
}

##</code><code>##

<shelf>
	<product>
		<title>widget1</title>
		<cost>0.10</cost>
		<rating>B</rating>
		<color>red</color>
		<color>blue</color>
		<color>green</color>
	</product>

	<product>
		<title>widget2</title>
		<cost>0.25</cost>
		<rating>S</rating>
		<color>pink</color>
		<color>gray</color>
		<color>orange</color>
	</product>

	<product>
		<title>widget3</title>
		<cost>0.50</cost>
		<rating>S</rating>
		<color>white</color>
	</product>
</shelf>

##</code><code>##

Widget: widget1
Rating: B
  Cost: 0.10
Colors: red, blue, green

Widget: widget2
Rating: S
  Cost: 0.25
Colors: pink, gray, orange

Widget: widget3
Rating: S
  Cost: 0.50
Colors: