E492: Not an editor command: W

I was looking at dotfiles on GitHub for something completely unrelated, and noticed this snippet by Gianni Chiappetta:

" Remap :W to :w
command W w

This will help when :W is accidentally typed instead of :w and Vim displays E492: Not an editor command: W. I occasionally do this when I'm making a lot of rapid changes and my finger lingers on the shift key.

Creating an alias with :command (or :com for short) will result in something slightly different to the real :w though, because it won't copy the arguments. Ingo Karkat posted a response to a Stack Overflow question about the same problem: Is there a way in vim to make :W to do the same thing as :w?.

But I think for your use case it’s best to define your own uppercase command-variants. The main challenge is to support all the options that the original one has:

command! -bang -range=% -complete=file -nargs=* W <line1>,<line2>write<bang> <args>

command! -bang Q quit<bang>

Adding the ! causes command to replace any existing mappings.

Although the simpler mapping will suffice for the more command mistake of hitting :W, it's interesting how far you can take a simple question about Vim configuration.