How to close the netrw buffer/window from any other window

Question

I would like to have the behavior where I can run :Vex<CR> when pressing <Tab> in normal mode:

nnoremap <Tab> :Vex<CR>

... to open the netrw file tree window and then I would like to close this window when I press <Tab> again in any other window in this tab. Is there some way how I can get the window ID when opening the netrw window and then close it by its ID in the same tab?

Answer 1

Update:

Lexplore bug mentioned below is fixed (also see the github comment), so you can now use a single mapping to toggle the netrw window:

nnoremap <Tab> :Lexplore<CR>

However, see the comment in the code, repeated invoking of Lexplore is not the intended use.

Original answer:

There is a Lexplore command to toggle a netrw window on the left-hand side. However, there is a bug that executing it multiple times will generate a lot of empty buffers.

For now, I think stimulate's answer is quite good. I created my single-function version based on that answer (I am not a vim expert, so not sure if this is better):

nnoremap <Tab> :call ToggleNetRW()<CR>
function ToggleNetRW()
    if exists("g:netrw_buffer") && bufexists(g:netrw_buffer)
        exe "bd".g:netrw_buffer | unlet g:netrw_buffer
    else
        Vexplore | let g:netrw_buffer=bufnr("%")
    endif
endfunction

Answer 2

The best I could come up with for now. It does not respect the current tab page yet, but maybe this could be achieved with using some kind of map data structure

nnoremap <Tab> :call OpenNetRW()<CR>

let g:netrw_buffer=0

function OpenNetRW()
  Vexplore
  let g:netrw_buffer=bufnr("%")
  nnoremap <Tab> :call CloseNetRW()<CR>
endfunction

function CloseNetRW()
  exe "bd".g:netrw_buffer
  let g:netrw_buffer=0
  nnoremap <Tab> :call OpenNetRW()<CR>
endfunction