Why do we need less than (<) and more than (>) here?

In your code, what happens if there are only 10 shirts? The display would allow the first 8, but the second page would not display because it would equal 10, not 16 (potentially as I don't remember the exact way $positionEnd is derived). Equal is much more fragile than greater than or less than.

Thanks for the reply, Ted. Yes, that does make sense for positionEnd, but I'm still wondering why it's needed for the positionStart. Won't the start position always be 1, 9 etc..? If it was greater than one of these numbers it wouldn't make sense as we've set the number of products per page to exactly 8.

Again, I do not remember exactly what it looks at for the numbers, but this type of data is usually stored in a database. There would be a unique key for each product. If you use a unique key in your code, it might not start at 1 as products are removed.

Hi Ted, I'm not sure it's looking at an id (or sku). I thought it was just taking the first 8 product in the array (the product data is stored in an array) as they are listed in the array.

Here's the code from shirts.php:

$start = (($current_page * $products_per_page) - $products_per_page) + 1;
$end = $current_page * $products_per_page;

$products = get_products_subset($start, $end);

The $start and $end variables are looking at the $current_page variable which from some previous lines of code produces a number, and then preforms the above calculations to decide what the start and end products should be for that page e.g. (1, 8), (9, 16). Those numbers are then passed into the this function as arguments:

function get_products_subset($positionStart, $positionEnd) {
    $subset = array();
    $all = get_products_all();
    $position = 0;

       foreach($all as $product) {
            $position ++;
             if ($position >= $positionStart && $position <= $positionEnd) {
                $subset[] = $product;
            }
        }
    return $subset;
}

As you can see the function goes through the product array and increments the position variable as it goes through each product, and when that position variable reaches the numbers that were passed into $positionStart and $positionEnd arguments, it puts those products into a subset array and returns it to the shirts.php page.

I don't see anything in this code that would suggest it looks at sku's or some kind of id?

I have looked at the code and started several answers, but the real answer is obvious once I really looked at the code we are talking about.

Is it possible for $position to equal BOTH $positionStart and $positionEnd AT THE SAME TIME? No. It is impossible. Since $positionStart and $positionEnd are not equal you have to use < and > for the code to work. The $position can equal one or the other, or be in between.

I forget the name of the mathematical theorem, but if a = b and b = c, then a = c. If $position = $positionStart and $position = $positionEnd, then $positionStart = $positionEnd. That cannot work for what we are trying to do.

Thanks Ted. I'm not sure I fully understand the mathematics there, but thanks for the explanation.