Prolog Challenge 3 Task 4 Extra Credit - Kaitlyn Jesmonth

Several additions to our blocks world like cones, ordering, the abilitiy to ask questions, and
the ability to refer to objects by location would expand our world to a bigger realm. In order
to expand on these ideas and to actually model this situation, multiple things would need to be added.
First and foremost, if we were to add cones to our model we would need to start by adding these
cones, one of each of the four colors, into the knowledge base. Once this is completed, then a new
rule would be needed in order to check and see what the object type is first before performing the
stack operation. If the object that is getting stacked on is a block, then it should proceed with
the stack operation. However, if it checks and finds out that the object getting stacked on is a
cone, then it should output some sort of error information stating that the operation could not be
performed. This new rule should only be put in place for the stack operation, as the put, pickup,
and unstack operations don't deal with placing a block or a cone on top of another one. When I was
thinking about modeling this situation, I realized that a level based approach might be best for
this scenario. Having some way of keep track of the objects on top of the stacks would be a useful
way to quickly verify if the stack operation could be performed. It might also help for some of the
instances where blocks that are trying to be moved are underneath another block/cone. Using a level
based heuristic would probably provide some ease.

As for keeping track of order, I think this would be a relatively simple thing to do. I think just
adding an extra variable to keep track of the placement of these objects would suffice. This variable
could be added to the validate rules. A number could be assigned from left to right in order to keep
track of order. For example, the block that is the farthest on the left would get a 1, the next one would
get a 2, and so on. Then once an object was moved, this number keeping track of position could update.
Let's say we are trying to move a cone to the right of another given block and stack it. We could use
the position of that given block and add 1 to the position value so that way it updates each time it
moves. Now this might seem slightly more difficult if there was no context being given. If we just said,
"stack the small blue block on the small red block" however, we would just assume the position of the small
red block and update it that way. Once this position was validated and updated, then the actual act
could be performed.

If we were to add the feature of asking hypothetical questions it would require some new features to
the parsing section of our model. We would need to account for the different grammar like question words
for example, and add them into our model. Once we are able to actually understand the question in our
model, then the next step would be to actually check if that hypothetical question can be answered.
This is very similar to what we did in task 1, by adding in error messages. I think that if we checked
all of the things we are checking now but just added a write yes or no to it, that would take care
of answering questions and verifying the questions being asked.

For the last part, if we implemented the ordering rules properly, then this would not be too difficult.
Referring to the location would just need the position to be checked. These types of sentences would need
to be accounted though for in the parsing so that way we would know that to the right of something means
adding 1 to the position value for example.

Overall, adding these features would be a nice thing to accomplish for the blocks world and would make the
user interaction a little bit more user friendly.