I've tried searching on google and other places, but can't seem to pin down anything solid. Is there any variation of the knapsack problem (or is it considered another problem entirely) where the weights/values are considered hidden until the full sequence is complete? I'm specifically thinking of such cases where (perhaps) the contribution of a single element is dependent on the configuration of its partner elements, and so assigning weights and values is incorrect until the whole "knapsack" has been loaded.
I'm not an expert on all existing problems, so apologies if this has just been formulated in another optimization problem entirely; I know it's related to the traveling salesman problem, but that still has the concept of distance between nodes, which again I'm interested in considering as hidden.