Need help interpreting some code

[timbeckham]

In the file, catalog/includes/classes/shopping_cart.php, there is a function, "add_cart" that has some code I cannot follow, and I would appreciate a little help. Here it is:

 

The third line of the function reads,

$products_id = tep_get_uprid($products_id, $attributes);

As I interpret it, tep_get_uprid() returns a string of the form,

"prid{option}value{option}value...", where prid is the original $products_id (an integer) and option/value are subarray elements from the attributes array. Here is my confusion - this new string value of $products_id is later used in the same function as though it is an integer (as a proper $products_id should be).

 

For example, later in the same function, the following code appears:

$this->contents[] = array($products_id);

$this->contents[$products_id] = array('qty' => $qty);

 

Later still in "add_cart", $products_id is used as a variable in SQL statements that insert records in the database. It is beyond me how a complicated string as above could be used in that way, instead of an integer. Nowhere else in OSC do I find $products_id used in this way.

 

I assume I am ignorant regarding some sort of array notation, but I am unable to find it in the PHP programming books I have (several). Would someone please educate me on this? Thanks in advance for your help.

 

Tim B.