My paper design addressed various editor operations that might take place, with consideration about whats selected, whats typed, and so on. Here are a couple of pages of those notes:
My general thinking was that I would compare two consecutive Snapshots, taking into account the position of the selections in both. The paper reasoning tempted me away from the simple idea of just comparing my lines. In the original chapter, I said:
Ive talked about comparing all the lines to see if they are differentand I was inclined to try that just to see if it works or if it is terribly inefficient. But I got to thinking about the selection...
Off I went, chasing a complex solution that didnt hang together, when I had a perfectly good next step staring me in the face. As HAL 9000 put it, it can only be attributable to human error.