Exchange Value of Variables with PHP and Perl

When exchanging the values of two variables, a third variable is generally constructed to temporarily hold one of the variables while the exchange is made. I'll show you a more elegant way.

For example, let's assume the variable $low contains the number 9 and the variable $high contains the number 4. $high should not be lower than $low. We want to exchange the values of those two numbers.

Here is one way to do it (identical coding with both Perl and PHP):

if($high < $low)
{
   $temp = $high;
   $high = $low;
   $low = $temp;
}

Here is a more elegant way with Perl.

($high,$low) = ($low,$high) if ($high < $low);

The more elegant way with PHP is similar to that provided for Perl. Here is the PHP:

if($high < $low) { list($high,$low) = array($low,$high); }

Will Bontrager