vim-airline: what is "! trailing[1]"
That means you have a trailing whitespace on the first line ([1]
).
You can add to your .vimrc
the following:
set list " Display unprintable characters f12 - switches
set listchars=tab:•\ ,trail:•,extends:»,precedes:« " Unprintable chars mapping
That'll display whitespace chars. You can toggle it with :set invlist
.
Airline is telling you that on line 1 you have trailing whitespace, which is usually something you want to get rid of.
So go to the line and delete it (1G$gelD
).
It’s a good feature, but you can turn it on/off with:
:AirlineToggleWhitespace
More info on trailing whitespace here.