I'm trying to set up some vars in a class and need to count an object in an array but am not doing it right obviously..

proceedurally it woud be this

PHP Code:
$productIDs = array(127879153);
$count count($productIDs); 
but that causes an error in this context.

PHP Code:
class myClass extends base {
    
$productIDs = array(127879153);
    
$count count($productIDs);

i've this and a few other variations below...
PHP Code:
$count count($this->productIDs); 
big thanks for any help on this...