to show whitespaces
:set listuse in combination with:
:set listchars=eol:$,nbsp:_,tab:>-,trail:~,extends:>,precedes:<- eol - character to show at the end of each line
- tab - Two characters to be used to show a tab
- trail - character to show for trailing spaces
- extends - character to show in the last column when the line continues beyond the right of the screen
- precedes - character to show in the first column when the line continues beyond the left of the screen
- conceal - character to show in place of concealed text, when conceal level is set to 1
- nbsp - character to show for a space