Logical OR in assignment

I once saw the use of OR (|) in assignment.

$x = $y | $z;

Does this use bitwise OR? I'm trying to see if I could use the above
expression in place of:

$x = is_null($y) ? $z : $y;

Jason Karns
~~~~~~~~~~~
The Ohio State University [www.osu.edu]
Computer Science & Engineering [www.cse.osu.edu]

--
No virus found in this outgoing message.
Checked by AVG Free Edition.
Version: 7.1.405 / Virus Database: 268.12.8/455 - Release Date: 9/22/2006

.