I have a
Product model, which belongs to many
Categories. I also have a
Discount model which belongs to many
I want to loop through a set of
Products (in a basket) and calculate a discount against those where the given
Category is the same as the
I don't think it's this I need https://laravel.com/docs/5.7/eloquent-relationships#has-many-through but rather some kind of IN method.