VIM: Show a 3 character border on left of window

Question

Context

I'm using the NERDTree plugin.

The one thing that irks me is the visual vertical border between the NERDTree itself and my code. I find it slightly annoying to read my code. My current setup looks something like:

........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________
........................#________________________________________________

where the ... = NERDTree, the _ = my actual code, and the ### = some vertical grey border.

Now, what I want is something like this:

........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________
........................#   ________________________________________________

The idea is that I somehow inject a 3 character border between the vertical divider of the NERDTre and the left of my actual code.

Now, I can almost achieve this via "set nu" -- except instead of getting spaces, I get a bunch of numbers. I would like something like "set nub", except instead of line numbers, I just get spaces.

Question:

How do I achieve the above?

Answer 1

You could use foldcolumn to create a gutter:

:set foldcolumn=3

If this adds fold markers to the gutter and you're not using folds at all, then you can set foldmethod to manual so that no folds are created automatically:

:set foldmethod=manual