PHP Assign array to variables

I'm not sure if my memory is wrong, but when I last used PHP (years ago), I vaguely remember doing something like this:

$firstVariable, $secondVariable = explode(' ', 'Foo Bar');

Note that the above is incorrect syntax, however in this example it would assign 'Foo' to $firstVariable, and 'Bar' to $secondVariable.

What is the correct syntax for this?

Thanks.