Ouch! It's the daily Vim time! I'll share with you the new Vim skills/knowledge I've learnt today :)
:e!drop all the changes of the current file.
vim -we use this pattern in bash to edit the output of another command. For instance:
info sed | vim - # use Vim to edit the output of the `info sed`
Cclear text after the cursor of the current line, which equals to the c+$. Kindly notice the difference between c+c and C, the former is to clear the whole line and enter insert mode but the latter is to remove text after the cursor and switch to insert mode.