https://robots.thoughtbot.com/vim-splits-move-faster-and-more-naturally
VIM NOTE:
"...and then with as many elements as there are "cols", each "row" becomes
[[nil, nil, nil],
[nil, nil, nil]
[nil, nil, nil]]
and starts looking more like a two dimensional grid which then gets populated with with new Cell objects:
[[Cell.new, Cell.new, Cell.new],
[Cell.new, Cell.new, Cell.new]
[Cell.new, Cell.new, Cell.new]]
To replace each "nil" with "Cell.new", v for Visual Mode, select the range of "nil"s to be replaced, then enter :, :'<,'>' pops up, and then enter "s/nil/Cell.new/g" so that the command line looks like :'<,'>'s/nil/Cell.new/g
or
:'<,'>'s/<to_be_replaced>/<replace_with>/g
(What do 's' and 'g' stand for/mean?)
http://vim.wikia.com/wiki/Switching_case_of_characters
http://stackoverflow.com/questions/2561418/how-to-comment-out-a-block-of-python-code-in-vim http://stackoverflow.com/questions/1676632/whats-a-quick-way-to-comment-uncomment-lines-in-vim