-bugs:
-monitor.rb:264:in `last': negative array size (ArgumentError)
- from monitor.rb:264:in `yield'
- from monitor.rb:157:in `print_buffer'
- from monitor.rb:95:in `move_resize'
- from monitor.rb:345:in `block in redraw_all'
- from monitor.rb:344:in `each'
- from monitor.rb:344:in `redraw_all'
- from monitor.rb:389:in `<main>'