Hello,

Please modify the documentaion on the Class to reflect the fact that
variables set in the classes must be given a value to prevent  
the "Undefined property:somevar" warning.

var $items;  // Items in our shopping cart

should be :
var $items = "";  // Items in our shopping cart
or
var $items = array();  // Items in our shopping cart
etc.

In fact, it appears to me that the variable declaration inside classes
is just about as imporatant as variable declaration anywhere in php scripts.
You either declare them or you don't, and to a large degree it doesn't
really affect your scripts, other than the warnings.

Furthermore , without $items given an initial value, it still has to be
checked inside the function using it to prevent the warnings, for example:

!empty($this->items) ? $this->items[] .= $num : $this->items[] = $num; 

So I don't see any "fatal error" causing reason to declare vars/attributes
outside of functions/methods in Classes.

The only reason I do see for setting vars outside of functions/methods in Classes
is to give it an initial value:
var $items = "";
And therefore  one does not have to do an isset() or empty() on the var
inside a method:
$this->items[] .= $num;  // no warning on this with:  var $items = "";


So the statement made in:
http://www.zend.com/zend/tut/class-intro.php
"All of the variables used by a class must be declared before any of the
class' functions including constructors" does not hold true for the reasons
I've given above above.

Thanks,
Bob