The benefit of substituting a scalar
variable name for a value is that we can then manipulate its
value. For example, you can "auto-increment" a scalar variable
using the "++" operator:
$number = 1;
print "$number\n";
$number++;
print "$number\n";
Perl would send the following to
standard output
1
2
You can also perform arithmetic such
as:
$item_subtotal = $item_price * $quantity;
$shipping_price = 39.99 * $quantity;
$grand_total = $item_subtotal +
$shipping_price;
Scalar variables are the meat and
potatoes of CGI. After all, translating between the client and
the Web server is essentially the formatting and the reformatting
of variables. Be prepared to see them used a lot.
