how to sudo in vim when you forgot to sudo from the command line.txt

do you ever try to edit some shit, like /etc/hosts or some apache
config, and forget to sudo? and then you have to f-ing exit vim and
re-run the command with sudo out in front of it? i hate that shit.

so here's a way to deal with that.
     
1. install the sudo.vim plugin
     mkdir -p ~/.vim/plugin && cd ~/.vim/plugin \
      && curl -o sudo.vim \
      'http://www.vim.org/scripts/download_script.php?src_id=3477'
     
2. expire sudo timestamp (for the purposes of demonstration)
     % sudo -k 
     
3. edit a file you can't write
     % vi /etc/hosts
  
in your vi session, it will tell you that it's read only.
   
  "/etc/hosts" [readonly] 6575L, 205583C
  
if you're at all like me, you generally miss that warning, and don't
realize until you start typing and then see this in red:

  -- INSERT -- W10: Warning: Changing a readonly file 

oh shit, now i have to fucking exit, then re-edit the file w/sudo.
shit on that.

5. but now that you're rolling with this plugin, just make your
changes. when you're done, type this:
   :wq! sudo:%
   
'%' completes to the pathname for the file you're editing. you will
be prompted for your password by sudo. enter that shit.

DUNZO.