Better Floods

Hello, loves! We need to improve Flooder, to allow constraining it to follow legitimate pathways. I am expecting it to be straightforward. Let’s review, for my benefit, how Flooder works. Flooder is an object that generates a sequence of cells and values, with the cells starting at a provided origin cell and expanding outward, producing candidate cells, each a single steps in the north, south, east, or west direction from a parent cell. Each such candidate may or may not be selected as part of the “frontier”, the set os cells that have bee produced and thus can act as sources for the next generation. Flooder acts as a generator and is intended for use in a for statement, such as we had this morning. We’ll look at that in just a moment. As production proceeds, a value function is called, provided the cell that is about to be produced, and the prior value, and it can return a new value. So far the only use we’ve had for the value has been to calculate a cumulative distance, such as we…