Sun, 12 Mar 2017 17:59:03 +0100 wenzelm clarified current_command: index refers to node content, negative index means first command;
(0) -30000 -10000 -3000 -1000 -300 -100 -30 -10 -1 +1 +10 +30 +100 +300 +1000 +3000 +10000 tip