I'm surprised there isn't much discussion of data structures here, as that would inform an undo algorithm. I infer from 'PieceTree' That this is a binary tree

I'm surprised there isn't much discussion of data structures here, as that would inform an undo algorithm. I infer from 'PieceTree' That this is a binary tree based piece chain. That makes undo really easy, especially character by character. Nice explantation of piece chains https://www.catch22.net/tuts/neatpad/piece-chains/ https://www.catch22.net/tuts/neatpad/piece-chains/